Leaderwise, I've had silly good luck running Cad Bane with his evasion bonus, with seemingly the first dozen shots from the enemy hitting nothing but air...and sometimes Cad Bane and his low health gets taken out with a single assist move, and Cad Bane seems like a complete waste.
assuming you're F2P, the best scoundrel team includes 88, Dengar, STHan and Lando. I'd say Cad Bane & his best in game evasion leader bonus for the 5th...but when that algorithm is not in your favor, makes me regret having him(which makes running Chewie of Broken Boba in a non-leader 5th spot seem like a decent move). I'm leveling up Gamorean Guard right now, I'm hoping he's a decent 5th.