There is no realistic reason to use the mouse for attacks in this game. You could have made the space key the attack button and had turn attacks be back+attack and it would have been the exact same thing except easier to control and controllable with one hand. I don't know why devs feel compelled to keep using mouse input for games like this, but it's pretty much just alienating a large portion of your audience that does not have an actual mouse for no particularly good reason. If this was a shooter it would sort of make sense, but otherwise it is just a poor design choice. If this had better controls you would have gotten a much higher rating.