I think combining spells would be fun too. Have a Spell Forge like the one in Grizzleheim. Put in two spells to make a hybrid spell. Cost one or more training points to make and learn. For example, combining a Nova with myth frog, get a nova that looks like a frog, or an Efreet with Forest Lord to make a Fire Lord, and they have some combo of attack abilities. Maybe you even pick from a list of new spell ability options to customize the hybrid spell best you can for your current wizard. Just a thought.