to avoid op it could be like this:
you can attack only in one dirrection at the time
if you attack with only one hand you do 3/4 of the normald dmg of the weapon
if you attack with both hands (=2weapons) that could do like 5/4 of the normal damage (the bonus damage could be added from the less damage doing weapon so attacking with 2hands at the same time you'll do 100% dmg of your most damage doing weapons pluss 1/4 of the less damage doing weapon)
and the blocking (as i've suggested before), etc. you press shift(or what ever else...) + left or right and show the dirrection.
and to really avoid the op it could be done that when blocking if you shift + left and show the dirrection to right, it wouldn't block.
and seriously, 2h are more op than this, they make little bit more damage(if my 5/4damage suggestion would be done) and they have more reach. ok they're little bit slower but the normal "you hit, i block then i hit, you block" thing would be still on.
