+1 for a (short term) road closed / avoid feature.
This morning, there was a major accident on a main trunk road on my way to work. A 10 mile stretch of dual-carriageway was closed by the police in both directions. There is no time for the police to put up detour signs. I got there just as the road was being closed. Meanwhile on Waze, there is no way to report that the road is closed, either to get Waze to re-route for yourself or to inform others (and you can't report the accident as you can't report incidents (or potentially road closures) not in your current exact location).
Luckily I know the local roads and knew where to go but for the first 3 miles of the detour, Waze was insisting I turn around and go back to the (closed) main road. If I didn't know the area, I'd be lost and blindly following traffic hoping they're going where I want to go.
Recently due to our bad weather, there have been a number of roads closed due to flooding or snow. Some are major roads, some minor. But if you come across one, maybe it's late in the evening, there are no diversion signs to follow, there's no traffic to follow, if you don't know the area you have to find somewhere to stop and examine the map and manually navigate as Waze just tries to send you back to the closed road. We need some way of not just reporting a closed road so Waze will warn you / re-route you before you even get close to the road, but also need to say how long it is for... no point reporting a road closed if your report will clear off Waze after only an hour, you might want to inform the system it will be there all morning, or the next 24 hours or maybe overnight roadworks...
Area Manager - southern Hampshire / W.Sussex, UK