one trick that will probably help a lot when using different classes would be keymaps. then, instead of a single key to a single action, it changes to a single key to a TYPE of action.

ie:
on your main, you have this keymap:
3 --> opening.salvo

and on your clones, you would have a different mapping for opening.slavo depending on the class

mage:
opening.salvo --> 3 (fireball)

priest:
opening.salvo --> 2 (smite)

warrior:
opening.salvo --> 5 (charge)

when you start thinking like this, it changes how you approach your key layouts. each class would have a normal key layout, and you would only be using keymaps for passing all keys.

keymaps are a bit more advanced... but i don't think you're the type to shy from tougher challenges, considering your first choice in a boxing group