My experience so far (after 3 campaigns - 2 as rebels) is that when there is a specific objective (not the timer or wounding/killing figures), that side usually has a much harder time winning.

I say that because - nearly without fail - in story and side missions the Imperial player had the advantage (or the outcomes were heavily in their favor), but any forced missions or Imperial side missions (where the imps had an objective and a potential reward), they were pretty easy to beat.

Just something to think about - from my experience - if there's a reward card in it for the winner, the mission will favor the opposing side. I've had to SERIOUSLY calculate sometimes turns in advance in order to thread my way to the objectives when there was something to win (like Luke, Han, Chewy, or a reward card of some kind)...

That's not to say the game is imbalanced - I know I'm not Sherlock Holmes when it comes to working out strategies. I actually enjoy being challenged so hard but sometimes after the 3rd or 4th crushing loss in a row, it can make one weary...

Just my $0.02