Maybe its best to start a new thread because I'm taking a different approach. He still needs to be able to hit in order to do (crit) damage. So...
2 levels of Theologian Cleric of Yamatsumi, Tetsubo, Strength Domain, and that oh so nice Enlarge Person spell.
Why 2 levels, you ask? Strength domain's Strength Surge power. Add Theologian's Focused Domain, and this gives a +2 enhancement to attack. Standard action (sucky) 3+WIS times per day. So...helpful.
Rest in Sensei Ki Mystic Monk. Heavy hitter doesn't need flurry, oh look...bardic advice. That's a competence bonus to attack rolls, nice. Ki Mystic at level 5 (so character level 7) allows us to reroll attack roll misses.
So BAB stinks, but I'd like to think the abilities make up for it. Thoughts?