Oh boy, a guy who betrays me in combat, is obnoxious, and overrides the outcome of the main characters decisions even if they both agree. That sounds like a fun guy to have in the group. I'm sure he'll last long in anyone's party, and won't be murdered in the wilderness and left to rot at the first opportunity.
EDIT: On a more general level, it's a bit too early to be planning out a 20-level plan for the stats build of your henchmen, because the stats the game is using are probably in the process of changing, in part thanks to feedback from these forums.
Last edited by Stabbey; 30/04/13 02:37 PM. Reason: too early