I'd go with:
Polymorpher
Unarmed Combatant
Summoning Master
Bard, Trap Master and Alchemist could have some decent secondary skills, but they wouldn't be trees I'd focus on first. I collected trap material in Beyond Divinity thinking I'd try them out at some point, but never did.
Juggernaut and Guardian don't sound particularly compelling (not generally playing barbarian or tank builds), at least not without actually comparing the skills to the normal warrior skills. For me, they'd be an option for a third platthrough (so good thing the replayability should be high).
