Yup, they are still very much functional, i do use them from time to time. I just don't need them that much yet because distances are small enough and there's some prominent landmarks, which makes navigating in daylight easy enough.
I do use them in the way you described though, mostly when sitting on the runway and warming up, in order to have a small flight plan ready by the time i'm about to take-off. I expect that if we were to start night raids they would see much more use, along with the compass and course setter in the cockpit.
As for my ramblings about future developments and the airstart question, it's not that i object to it out of principle. I just think it would be interesting to have the raid take place in its entirety even if under AI control if not enough players participate in it, simply because it would give other players the means to change the outcome. For example, the opposing team might have sent some Jabo 190s to bomb those heavies before they take off, or they might be spotted over the North Sea by chance, the intel gets passed on and a better defence is organized, etc.