Lot of classes you can simply the process with the same button...

Same goes with warrior and 3 casters and healer, healing will always be seperate unless you wanna burn healing mana unnecssarily...

Warrior sunder can be associated with mage fireball, warlock shadowbolt, and a shaman nuke... but of course you'll want to have 2 sets of sunders, one so that you BUILD up aggro, and the other where you use it to keep aggro while you're nuking. That's general concept... everyone will tweak for their own use.