My team of choice here is SpecForce Infiltrator (Tier 5 Rebel Soldier), Leia, Gotal Hunter and either Han Solo, IG-88 or Chewbacca. This is a fun team because 3 out of 4 of them can attack multiple opponents, which is perfect for expediting those tedious missions. I wouldn't use this team for Arena Battles though. Make sure you check out the way that SpecForce Infiltrator uses his awesome Thermal Detonator -- it's quite entertaining.
Weapon Tier 5 Promotion Gameplay
Weapon Tier 5 Training Gameplay
Armor Tier 5 Training Gameplay
Mechanical Tier 5 Training Gameplay
Survival Tier 4 Training Gameplay