Before you completely dismiss this idea let me explain. You can only use your collected minerals in place of CE only when in missions or the arcade. You wouldn't be able to use this at ANY alchemy station or Kozma shop at any of the subtowns or terminals (also wouldn't be used in the supply depot you can bring up while on the floor). Using it in Haven is of course out of the question.
All of this limits you to Mecha knights, Turrets, and Energy gates (danger or prize room).
That would actually be really helpful :O
Instead of wasting precious ce, we could potentially use the power of the absolutely no use valestone and moonstone!
*Gives Holy-Nightmare the cookie he deserves*