In pretty much all of the new user testing, users pick up the device and expect to repeatedly tap on the attack or skill buttons to fire them off. Almost no one intuitively grasped auto attack. I understand the concern over cramped fingers for longer gameplay. However, given the hectic gameplay in Arcane with multiple groups of eneimies, I'm not sure that auto attack would significantly reduce the number of taps you're going to make in any one combat.