NOOOOOOO!!!!!!  I've said this before and I'll say it again.  FS is a civilian flgiht simulator.  The purpose is not to kill or crash or anything else.  It is for enjoying the thrill of flying and for having the oppurtunity to fly a plane you wouldn't get to in real life.  Making it anything else would diminish it.  Whatever they do to CFS, changing FS in the way you describe would destroy it.

The correct airports for the correct period would be the smallest problem. Actually that can allready be done since FS scenery supports dates, hence the Berlin Wall.
Problem would be performance, FS couldn't handle all the objects required for a decend combat sim, in particular since the bgl code is comparably pretty darn old and slow.
I think CFS3 was a move into the right direction, just half-hearted finished.