So one thing that I’ve seen is that as of right now the spells that can be used now only require 2 strokes to cast. What I would like to suggest is a spellcrafting system. Basically, each spell that can be made has several components to them.
For example: Say I wanted to have a fire spell that affects an area. To ‘discover’ the spell, I would need to use one ‘fire’ component and one ‘area’ component. If I wanted to have it do damage (to the area) over time, I would add a ‘damage over time’ component. If I wanted to just get rid of the AOE part of the spell, I could just remove the AOE component. Or I could keep the AOE component and add a ‘projectile’ component so I’d be able to shoot it and have it do area damage. Etc, Etc.
I figure that this would work relative to how spellcasting normally is in videogames. The bigger and more complex your spells get, the longer it takes for you to cast the spell.
By doing this, many spells can be unique and if done properly, fairly balanced as well. For example, taking the spells from above, adding an area component slightly reduces damage as a tradeoff for area damage, and the damage over time component splits the overall damage into several parts.
But in the end this is just a suggestion. It might be difficult to implement, and I have little knowledge of how a system such as this would work.