In my opinion, a shield bash shouldn't be a dash + bashing action. I believe this should be a true bash with your shield with minimal positional movement.
On the idea of adding new actions, (I believe) many players would probably be unable to cope with extra buttons and things due to not having a gaming mouse with extra buttons, or not wanting to have to press extra buttons on the keyboard. Part of SK's selling point is its simplicity of controls and being (in my opinion) a relaxing game. By adding this functionality, I'd feel left out if I was not using it. If OOO can work around this problem, there's no reason not to widen gameplay.
good idea , hope it doesn't turn the game to being extremely skill intensive like starcraft 2 or terraria , in which case i won't be playing it