I had always figured Boba Fett and Han Solo had some past not mentioned in the films, as to why fett hates solo.

Fett hating Jedi was explained in the prequels since jango was beheaded by mace windu.

I always kind of saw Fett as doing this job for the money more like a mercenary, in fact the mandalorians are almost exclusively portrayed as a warrior race with an honor code, and many are mercenaries.

I also always thought he sided with the empire for some reason other than the fact that it pays more.

I always figured it would have made sense for Fett to capture Luke Skywalker, since both the empire wanted him dead or alive, and vader wanted him alive.