There's only small amount left hand items, like the shield you can only get the round standard ones and you can't craft the magic book that are left hand item.
So I believe we need of more them, for example shield should have advance version like armors too.
daggers should be able to equip with left and right hand for dual wielding (If the right hand weapon isn't dagger then you can't equip it) I would also like dual wielding to be affected by strong arm body mod if you like to dual wield medium size weapons like sword or mace.