I'm new to SWR however in the few games I have played as the rebels I had a real issue in doing the obvious sabotage mission and other combat led missions due to Darth Vader, Boba Fett and my opponent going after my combat based leaders.

As a backup I would use the diplomacy mission not just to flip neutral systems to the rebellion but deploy in imperial held systems where he could build capital ships. I found it easier to beat the empire with diplomacy if opposed and the effect if successful is to gain one loyalty meaning the world becomes subjected denying the empire of its star destroyer production in that system. It also annoyed the **** out of my opponent.

Now I dont have the card to hand as it's packed in the box but I'm sure You can play it in any populas system so checking I'm using it correctly?

Also is this a viable strategy to use or am I missing some deeper strategies that would counter it if my opponent had a few more games under his belt?

I assume you are talking about the cards "Establish Trade Relations" a 3 - diplomacy card which gains you loyalty or the starter card "Build Alliance" a 1 - diplomacy card. Each of these can give you loyalty in a system even if it has imperial troops which will block the right most resource icon. Yes a rebel player can do this and it can be very annoying but when playing against a veteran imperial player you need to be very careful to avoid having your leader captures as your opponent seems to favor characters with high Spec. Ops rating (fist), and this is used on the capture card. The imperial player can also turn your leader to the dark side with the "lure of the Dark Side" card which can be quite detrimental. If an imperial player plays their cards correctly they can take up to 3 of your rebel heroes. One with "Lure of the Dark Side" giving your hero to their pool, one with "Carbon Freezing", and one with the "Capture Rebel Operative" card which is a starter card for the Imperial player. Also, if you ever play the imperial player I would suggest always leaving a single unit behind when crossing the board taking one system at a time to prevent losing all of your systems to the diplomacy effect since the starter empire card requires a unit on the planet to gain loyalty. Also, you mentioned that the imperial player took Boba and focused on capturing systems, because Boba does not have a tactic values he cannot move troops so people who pick him often assign him to the capture card since he can only resolve mission cards. This game has quite a bit of depth and there are various strategies that either player can take to win or counter their opponent.

hopefully this helped

Yeah certainly did, as I said I'm new to the game so just working out what strategies to use.

Only reason I have played as the rebels twice is because I pulled them out the hat twice but looking forward to playing as imperials. Seems that getting out the traps early and taking the initiative is important, I'm both my games the imperials tended to just react to my tactics and forgot that their goal should be expand and dominate. Looking forward to getting a chance to play as the impeials ?

I was playing with a friend of mine for the first time and his statement was "to heck with Luke Skywalker, Mon Mothma is the real threat."

Yeah I'm due to play as the empire next time round and Mon Mothma is a huge target for me.

Going to make sure I oppose their diplomatic efforts whilst being aggressive as possible with my forces.