Thanks for that. I've been meaning to check on ramp naming (I have simply copied the format from all the local ones ). I think I have fixed all those now.

I agree, I would not normally consider the extra information but this particular RA can be difficult to navigate when you know where you are going. When you throw in that the BGS before the RA have city names but when you get there they are gone (or say something different as you pointed out in the case of Becketts Rd - I missed that one), it made sense to add that little bit of extra info into the TTS for the two directions that don't have ramps to help guide you. Essentially giving the information a ramp would if there was one.

Wayfinders should be used where the information provided through routing in the app may be insufficient. Typically this happens on Motorways and higher rank roads.

The only reason I can see to add wayfinders to roundabouts or other local roads, is when the sign does not match the roadname exit on the sign. If the exit road matches the sign, but doesn't include the cityname, the wayfinder is not really useful. The other use of wayfinders is to provide missing TTS instructions where there normally would not be.

Turning to your examples:
1) Segments to ramps.
This is fine, however the correct naming standard for ramps is (in this case) "to Old Northern Rd to Albany Creek"

2) Naming on these three segments.
The Rode Rd one is not necessary as there is a little green sign which purely says "Rode Rd <".
The Old Northern Rd to Everton Park / City ramp is fine, but please remember the naming convention as described above (wiki link below).
The SR40 example is fine, this is a bit of an exception to the naming standard as the sign is for a triple exit roundabout which isn't really covered by the wiki article. The TTS provided by this should be fine.

3) Wayfinder segments to these two roads.
Queens Rd one isn't necessary as there is a small green sign on the roundabout saying "Queens Rd <"
SR40 Beckett Rd one is actually flat out wrong and could be misleading, the small green sign on the roundabout says "Beckett Rd to Northern Suburbs"

Naming convention for ramps with no fork (TTS instructions).