We'd be better equipped to answer you question if we know why you don't enjoy the base game when playing with only 2 players. Can you provide some insight on that front?
Indeed, though it seems to be a pretty common opinion about the game.
I find the pace of the game better and the interactions a lot more fun with more people. I did not play many times with 2 players, but it felt like strategies and choices did not matter as much as with 4 people.
I am not saying it's bad, I was just wondering what was your experience with 2players in the core game vs rebellion.