I really just wanted to reference Vanish-Doom/X-Zone. The end goal is to set up a bunch of elemental effects on some mobs, and then combo some big damage effects off of them to regain your healing potion stock.

You probably could make most of these into weaponskills or instant casts. I do think that having potions (healing or damage) be somehow limited by a total stock is still necessary, because that's what differentiates items from traditional spells. This is just brainstorming, you can flip around the combinations however you want. I've just laid out some of the healing and damage items that tend to recur in the series.