I have the dream that a 3rd party would do a much smaller map just for helo ops. I guess on huge map`s you do not have enough ressorces to put more details on trees (and it`s collision model) and environment and keep fps high enough. The forest, we have seen on that vid/pic with the upcoming Mirage over Nevada map, isn`t that dense, obviously.
There is a dedicated helo game where the trees were very dense and collidable (i.e. Amazon forest), though AI could look and even fire trough it. We probably won`t see all these features you mentioned in the near future.