I think you shouldn't be able to use a potion when your health is full because the other day I was in a tower and was low on health and i clicked a potion, then my mouse automatically clicked the other two. My friend and I didn't finish it because of that. And, I wasted about 3000 gold.
Why anybody would pay to refill potions when it takes about 30 seconds of gameplay to fill one is beyond me. I could possibly see it when deep into Celestia, when gold is plentiful, but it seems like a waste to me earlier in the game.
Actually, eliminating frustrating misclicks is very much a good reason for a change. Though, it should only apply when both health and mana are full, not just health, to prevent players from drinking two potions with a double click.
Actually there are dungeons where there are not means to fill up. You have to fight and fight again and hope you are healthy enough after each to fight the next. There are a few like this from krok up and so potions fill you up because you my get past the hentchmen but the boss is usually a health drainer.
