many rpgs do this, even the old school ones. Spell vs. Abilities/Skills. Above mentioned bash and charge, or even things like rend armor or hamstring. Some use "Stamina" or "skill points" or "energy" instead of mana (as well as cooldowns) In one of the tutorials (video) they used a summoned bear and the bear did a maul attack which stunned the opponent for a turn. It was an ability, not a spell, but it cost mana. I see your point about not having mana be the only limitation to prevent spamming. 
karma! Another aspect to consider is deminishing returns. Sometimes getting hit with the same thing over and over again builds up a tolerance against it. I.E. stunning a stunned creature doesn't make sense, so they did things like "root" or "k.o." or "sleep" as well, afflict them with several things. Or as above mentioned if you get hit with fireball after fireball after fireball, once you're on fire, you're on fire, you might burn a little faster but it shouldn't do as much damage)
