Lord Sovereign
The resident Britbong
Vader wouldn't do so well at puzzles (not to knock his intelligence at all) but he's probably the best battlefield tactician present, an absolute wrecking ball in combat, and his stormtroopers will be quite effective under his command (probably 501st troopers as well).
He's probably someone the more manipulative villains would look to get on side as quickly as possible.
He's probably someone the more manipulative villains would look to get on side as quickly as possible.