I think they shouldn't just readdress spell animations, but also their effect in battle. For example, as you mentioned, stone could be used as a way to knock back the enemy, and not just a way to deal earth damage. Or perhaps it could be used as a way to petrify the mob in a layer of stone.

I think there should also be spells which can create barriers, for example, a wall of ice... or a spell which creates a slippery area of ice around the player where mobs movement speed is decreased. Things like this would help make the battles more situational rather than systematic: buff, debuff, tank, spank.

Making something look big, as minidrax said, isn't going to resolve the issue of combat. They need to be more inventive about possible strategies. For example, maybe the wall of ice could prevent a line-of-sight between the mob and the player, thereby rendering the mob unable to cast ranged attacks/magic.

Animations are only half the issue.