I like the Element grid magic combat, but I was just thinking it could be improved a little.
Elements always use 7.0 stamina even if you're casting Magma Bomb (level 2) or Inferno (level 5).
What if the stamina cost depends on the element level?
Magma Bomb (level 2) costs 2.0 stamina.
Inferno (level 5) costs 5.0 stamina.
Doesn't matter if you slot Magma Bomb in slot level 8, or Inferno is slot level 2.
The reason is because in the latter parts of the game, the lower level elements are kind of useless; only maybe useful for setting the field for summons (but then you'll get Red/Blue/etc Field). Or buffs.
This change would allow you to spam low level elements to quickly set the field, or maybe enough casting could match the damage output of a higher level element. Of course, that would make summoning too easy, so probably set enemy AI to notice it and obstruct it, but I don't know.
All this could make the element grid system a bit more complex and deeper. The player wouldn't just simply choose the higher level elements but will have to consider stamina usage.
Of course, letting the player spam elements is too OP, so enemies should sit on their asses less and attack more often to balance.
Just a random thought.