See, to aim like a mouse was my first thought. However, I also then thought about controller and realized this wouldn't really work. Truth be told, I don't think there could be a "good" aiming system for controller because, simply put, nothing is better at aiming than a mouse. The only time I find controller can match is when it has motion controls.
That said, I think the game might be better served by taking a step and asking if aimed weapons is even the way to go. What about if every attack was just in a fix position relative to the character. So for a bow and arrow, maybe on a 45 degree angle relative to the character? That way, it behave predictably and players can more easily know what to expect from it.