Since this discussion took a "barb and paladin in a BG3 sandbox with magic items" turn, one must mention the item to rule them all... WYVERN POISON.
Either the barb or the paladin has it....but not both. Muhahaha.
Oath of the ancients can heal as a bonus action, though. If we're optimizing the paladin, any subclass can smite the barb ONCE as a bonus action.
Of course, devotion can make their weapon magic pre combat and negate any and all physical resistance. Also gaining better hit chance while doing so. Ancients can't, so devotion might be better here? 🤔
They can also bless pre combat. Since we're counting throwables as allowed, might as well go all in? Everyone has haste potions, go, go, go!
