I think this has been said before, but I am too lazy to read all 70 pages of this thread
. When having trade alliance (or higher) with someone, you should be able to "break" trade alliance without it causing any battles. If you break treaty now, your planets fight if you have planets/fleets in same location. It should be able to get decreased into "non aggression pact" instead of plain nothing. This way a lot of execuses would be avoided (in PBW atleast).