Good question.
Most importantly, you should have the fastest speed on Vader compared to other Vader. That gives your team the first move.
You can switch in han solo for offense if your Vader is slower to stun their Vader.
Two tanks is a good idea, with 1 of them pretaunt. Like shoretrooper and go.
Other than that, you just have to look at the successful empire teams. Mainly, they the YouTubers are using EP, Vader, thrawn, gk +1. The best +1 are DN, imperial probe droid, shoretrooper. I hear stark is also good. Tarkin is good as a start, but I don't know if he can be as good as DN or IPD.
