I have a couple of thoughts and I know that will not surprise some.

• Generally, I do not mind locking completed works. However, locking with RSEL or other scripts seems to be self defeating in our attempts to make the map better.
• I cannot think of a single PS that is really different than and street next to it. I really think a completed street locked to 2 is not terrible. I'm not so sure I see added value in locking one way segments higher than their two way cousins. I know I am not more inclined to break a one way or change it from one way than the opposite. In fact, I would bet the opposite is really the case. If something is marked one way I would likely look in SV for signage where a two way I would assume to be correct. If said signage did not exist, but it was a real one way, I would expect an overlock and maybe a note.
• I think areas outside our core areas where we have less editor coverage are good candidates for a -1 locking approach. In MD, that would be western, southern and eastern MD. In VA, the southern rural areas screams out.
• As the maps mature and we lock more, both segments and places, we need to come up with methods to bring the new editors up to R2 and R3 or there will be no editors at some point. A new editor that lives and drives inside the Baltimore or DC beltways still has much to offer but will find it harder and harder to get edits and we are making AM promotion tougher too. I routinely struggle to come up with suggestions for editors to get their R2 edits done. SLs have been a godsent in this area but they will be gone all too soon and get tedious if the editor is doing it right, especially without scripts since we try not to lose the editor right via complexity.
• The 100lb gorilla in the room, at least in my mind, is the resulting increase in unlock requests and the way they are handled. At least in MD & VA, people gravitate to the GHOs for unlocks but outsiders unlocking without a pre & post examination of the area. I have gotten ribbed for reluctance to unlock something locked above the norm as I wonder why the lock is elevated, especially when done by particular editors who don't overlock. A segment (St, PS, mH for this example) locked at R4 or R5 will easily get an unlock for a well meaning editor well into R2 or early in R3 when it normally would never be locked that high in this area. Personally, I would prefer that R5+ locked entities be done by someone at that level as opposed to unlocking, unless there is something special going on requiring large numbers of edits (simple items such as SLs excluded). Maybe our segment locking system needs approvals like places.
• Having said all of that, we have to remember that increasing locks means the higher levels HAVE to manage those entities. An airport locked at R5 with a large number of pending edits means the lock is too high and/or someone has to dedicate time to those tasks.

Please note that I am from outside of the region, however, I do have experience trying to work with urban and rural editors.

For Rural Areas vs Urban Areas, I don't believe that having a lower lock is intended necessarily meant to indicate that they are any less important, but rather, as jr1982jr stated, to allow the lower rank editors the ability to work towards their promotion.

The difficulty is that people are locked within 1 mile of their driven routes given that they were able to maintain good cellular signal connection the enter drive in order to even get their editable area. If they live in more rural area, that be default would mean less roads for them to edit. The grind to level 2 I still believe is still doable/manageable at 3000 edits (though I have seen some editors throttled at level 1!) however uplocking the rural roads, especially the streets and primary streets, makes it incredibly frustrating because you can not even then add house numbers and as a new editor coming into the WME, you just have to pray and hope that there is a CM/SM/AM in your area that you can reach out to (remember, new editors do not have the WME Chat Addon, they do not know how to ping CM's, they most likely don't know to private message, may not even be aware of the forum, but may contain a willingness to learn and enthusiasm to take care of the map - indeed, there are many times I've come across in a rural area that was excited to make contact stating "There's probably not another map editor within miles of where I live!") and if you don't, probably will just give up.

I'm not saying mH/MH should be any lower than 3 as to get to 3 edit counts are not the way to promote. If anything, I would be curious to know why there is a need for MH's to be to 4 since in order to get to 3 you would need to have been reviewed by the RC to be promoted and therefore have at least made contact with the community and be reviewed and scrutinized - meaning at least I would hope when you get to 3, you would take a bit of time/hesitance to just mass edit a road on a whim. Since feelings were asked for in terms of rural vs urban, those are mine.

As an aside, I also do agree that locking one way roads higher is weird. I'm fine with things being uplocked if they are uplocked for a reason, and agree with jr1982jr that new editors tend to try to inappropriately divide roads than try to inappropriately undivided roads.

Just a a quick note on one-way +1s:
The reasoning behind the one-way +1 has more to do with marking them as "reviewed and confirmed" as one-way rather than protecting them from being 'undivided'.

Basically if I go to a basemap area and see a one-way street at L2, I know a knowledgable (wiki reading, lock following) editor took the time to verify it was correctly defined on the map, then lock it.

This wasn't really mean to protect divided boulevards in suburbia, and typically they don't need to be divided one-way couplets anyway.

Thank you for the posts, please continue so we can work through the details.
I would like to offer my thoughts on the rural/urban view:
Consider that the long rural routes between destinations, are they not as important as any that you would see in an urban area? Indeed they may be more important as a break in one of these routes would cause a major reroute.
It has been my experience that an editor can gain editing area in rural locations by driving, it is then open to break a route for an inexperienced editor and may go unnoticed for a period of time.
Does that not justify the lock standard.
Base map areas are not locked as they are untouched, and should not be locked with auto scripting, they should be worked from main routes, to include connecting segments, and then down the ladder of secondary routes, then locked upon completion for security.
The MAR region does have enough active leaders to handle unlocks, I am open to comments of why rural should be treated differently than urban areas.

Your thoughts and suggestions are well stated, I see that some have concerns regarding unlocks, has that really been an issue for our region?
As to locking in rural areas, if the segment is completed and then locked, is there anything else needed other than a possible change to the area or a closure? These should be handled by unlock requests.
Please note that it is common practice for editors to request AM areas that are urban, always consider a rural/basemap or unattended area for an AM request, you can either scan around to find them or ask the SMs, they can lead you to these areas.
I believe we have always had the thought process that if an editor wants to work an area, a large unlock is possible for a period of time, provided the editor will indeed work on them. These types of unlocks should not be expansive, always good to have a review of the work done before moving on and relocking the initial area.
We all started editing and learned through trial and error, I have found that mentoring, whether formal or informal benefits all, and I believe we do a great job of identifying and contacting new editors, this in itself should allow for consistent locks that protect the hard work that has already been done. If an area is found that is in bad shape, we can assess the area, complete and lock the major routes, and lower the other segments for a junior editor to have access, and then lock as we go, but I still have not been swayed to believe there is benefit to a separate rural/urban set of standards. But I am keeping an open mind.....

Just wanted to highlight two majorly important sentences in the OP that appear to have been overlooked by a few. Please consider all the implications of:

As always, road segments should not be locked unless they have been reviewed to ensure that all their properties are correct. This is general guidance, so segments may locked at different ranks in particular circumstances.

I used to be hard core against locks and was quite likely the major driver for the Rural locks in the first place (in Virginia and eventually WV). Then I considered the implications of the first sentence above. MH should not be set to L4 until it has been reviewed and all properties are correct (that would include speed limits, now). Seems like we shouldn't get a whole lot of unlock requests (which are dealt with pretty quickly in the GHO) in Urban nor Rural areas as long as we follow that standard + the MH that have not been reviewed yet due to Rural or what have you...shouldn't be locked up so still available for anyone to review and correct.

I can't emphasize strongly enough...Please do NOT mass edit with the auto-lock bookmarklet!!

Second sentence is important, too. These general guidelines are the MINIMUM lock standards. Any editor can set a given segment as high as their level (or request help from higher up if needed) for special circumstances. I am, personally, very hesitant to uplock above the standards, but will do it if the need arises. Pretty sure most of the currently active senior editors in MAR feel the same...so when we run across a downlock request or segment above the std...makes us look twice and/or ask why?

I'm not so sure I agree with MH at L4 in all areas. It makes sense in urban areas like Baltimore City and DC, where there are more drivers and therefore more editors. Rural areas like Western Maryland and West Virginia not so much, maybe L3.

Perhaps make a determination on this on a per-county basis?

Also, perhaps, PS at 1 to avoid discouraging new editors -- we want new editors to stick around so we have more people to become AMs and SMs. We don't want them to say "Well I can't do anything!" and give up.

Reasonable people could argue either way, I suppose. I'm OK with this locking standard. I suppose I'd better get cracking on getting my rank up to L4.

Well, that's a determination that ought to be made by someone who lives in or otherwise is intimately familiar with the area -- such as an SM or AM.

I live in one of my managed areas. It's fairly rural. MD-140 is classed MH and MD-832 is classed mH. Break something on 140 and you'd cause some minor re-routing. Break something on 832 and I don't think anyone would care or notice, unless they were going somewhere on 832. Lock 140 at R4 and you lock me out of editing on 140, in an area I both live in and manage.

Also, here in Maryland, SHA over-classes a lot of roads on their official route logs, in my opinion. About a year back there was a major effort to make the FC match what was in SHA and county route logs. I see no reason why MD-194 is classed MH through Taneytown where it is mH elsewhere. MD-800 should be classed as mH according to the SHA route logs but I think PS or even street is OK (I've left it at PS just because it's a signed state highway, but really it should be Street).

I gained a lot of editing area in West Virginia over the weekend by attending a roadgeek meetup where we driove on Corridor H and the roads it is to replace. I threw a bunch of speed limits on US-33, US-48, US-219, and WV-32 where I saw that there were none, but I wasn't really doing any heavy-handed editing. Still, I was editing enough that A WV SM took notice and sent me a welcome and an invite to the WV GHO.

If someone broke US-219 that would cause a major, multi-mile re-routing. Ditto WV-32, but 32 is only mH. If we say "if someone breaks this road and it causes a significant re-routing then we should lock it at L4 or L5." By that logic, you leave WV-32 as mH but lock it at R4. Now, suppose you get some West Virginian Baby Wazer editing the map, and they live near WV-32, and they get frustrated because they can only edit the side roads? Then they leave and don't ever edit again, content to just use Waze as an app for directions and traffic avoidance.

I guess what I'm saying here is that in order for this locking standard to work as intended, we need to really think about whether our FCs are correct in some areas. We also need to give SMs and AMs the power and authority to override the locking standards with good reasons. But what, then, is the point of having a standard, if nearly every road is an exception to it?

I'm glad for this thread, so we can work out these kinks before a standard goes into place.

(Edit: used RC where I meant FC. That could have caused some confusion. Corrected the error.)

With the speed that downlocks are available these days, having MH at 4 should not be a problem for community connected R3 editors. Just speaking from experience with the South Atlantic Region, we have had MH standard at 4 for over a year now. As it was mentioned before the road should not be locked until it is complete and correct, so rural areas that still need a lot of work won't be unavailable to editors trying fix the map and work their way up they rank system. What it does provide is an extra set of eyes on a road type that we feel is very important. An R4 lock does not prohibit lower ranked editors from fixing issues, but it gives higher ranked editors a chance to review and ensure there are no stray restrictions that might have been missed, for example. It happens to the best of us, and a second look is extremely helpful in this case.