Indded. Having a generic action (all classes can use) named "Auto-Attack" would be more than enough...if not equipped it keep working just like it does now, triggering when monster is in melee range...but if you equip the action you will have to use the action to start/stop auto-attacking...if that's the case they can even change it to a toggle system like defender, with the action having an effect icon listed when AA is up.