Unless they changed the mechanics, Dual Wield is probably the best in any given situation, especially if you have two weapons with 3 enchant slots. The reasoning is that the game actually applies all enchantments and damage bonuses to BOTH weapons.
Let's say your weapons are:
Sword A
5% crit rate
20 - 30 damage / 20 - 30 magic damage
3 enchants:
-Inc Damage 10 (+27)
-In Mag Damage 10 (+27)
-Butchery 10 (+11% crit rate)
Sword B
5% crit rate
20 - 30 damage / 20 - 30 magic damage
3 enchants:
-Inc Damage 10 (+27)
-In Mag Damage 10 (+27)
-Butchery 10 (+11% crit rate)
And then have, say, four Divine Damage Charms (+10 melee damage) on other equipment.
BOTH weapons' enchantments, and all four damage charms are applied to BOTH weapons. That means the final damage output is like so:
20 - 30 base melee damage
+40 (charms)
+54 (enchants)
= 114 - 124 melee damage per weapon.
20 - 30 base magic damage
+54 (enchants)
=74 - 84 magic damage per weapon.
228 - 248 total melee damage; 148 - 168 total magic damage
And as for crit rate, let's assume Deathblow is maxed at level 15 (for ED, at least - dunno about FoV):
5% crit rate base
+22% (enchants)
+30% (deathblow)
So we have 57% crit rate total per weapon
So, in conclusion, the dual wield mechanics mean that in the above you'd need a weapon with approx. TEN TIMES the melee damage that two one-handed weapons provide to make any other weapon type viable over dual wielding. Even on a per-weapon basis, it's around three times stronger than it would be otherwise, just by throwing on another weapon, fully enchanted. Not to mention, 2H weapons have a much larger damage range.
They might've fixed this, so take it with a grain of salt for now, but if nothing else, the critical rate it can create is ridiculous.
