I would like to ask this functinality to be added in near future, I think it's needed to give maps that little fine touches of detail currently almost impossible. (only by making it tilted in source files)
It's needed for example to pivot trafic ligths and signs at whip arms. Also the give maps nice details it highly nessecary, otherwise anyone building a map need to go over the whole chaging things after the maps already was (partly) finished.
Also it would be nice if X and Y rotation would work for attachpoints, the Z rotation setting for attachpoints already seems to work fine.