Astrotrain isn't too evil for friends! If I said that I was lying. He's friends with Blitzwing! He probably has other 'Con friends, too; I strongly suspect he gets together with Long Haul for a cube of energon (alien alcohol! it is canon!) and complains about having to haul things all the time.

I feel though that he is probably too evil to make friends with the Thomas the Tank Engine crowd. He would probably think they were a bunch of idealistic Autobot wimps.

ETA: He wasn't having sex with Perceptor, though. That was, in fact, Skyfire, who is a space shuttle who is not evil. Except when katarik is writing him.