the shield ac is clearly to represent divine shield (cha mod/2 shield ac for toon such as this which meets prereq of lacking monk ac + quasi status); hence it changes from +10 @ 60 (50 cha) to +12 @ 80 (54 cha)
Sorry I was unaware that DS gives shield AC Learn something new everyday.
STR: 14 (20) DEX: 14 CON: 10 -Those were your original stats INT: 14 WIS: 12 (16) CHA: 14 (18)
What I would recommend is taking ftr as your first level so you can put your wisdom to 8 [At a cost of a few slots but meh]
Choice of weapon matters less now with the OP dual-damage types out. Maul, scythe, greatsword, halberd, etc all work - pick your favorite. Weapon type is of less consequence now; go with what you think looks cool and fits you in terms of possessions, style, damage type and crit modifier. Slashing, piercing and bludgeoning all have their perks and you can PWA a complementing damage type weapon on top and you're set - or just use a complementing damage type without weapon feats against some easy to hit targets like oozes and trees (slashing) in case you pick a non-slashing weapon.
For this particular build, fitting exotic weapon proficiency would cost either GWF or 2 great strength feats (freeing up another feat for something else) or pushing one GSTR feat to Paragon levels, so an exotic weapon like Scythe will have its price, but not impossible to fit in. Especially for a build reinced close to 80 with doubledemi and PL bonuses, fitting exotic proficiency at cost of greater weapon focus wouldn't be a big deal.