I'm not someone who has played Soku a lot, but even I can tell this is a bad idea. This is more or less going "hey, you know the danmaku elements which are meant for zoning and sometimes damage which are limited by spirit for a reason? LET'S FOCUS AROUND THAT AND REMOVE THOSE INTENTIONAL LIMITS."
Plus you're saying that you can more or less spam spell cards, which is the same as if you could always spam your supers in ANY fighting game. No, no, they're supers for a REASON.
Just no, no, bad idea, please, it's fine as it is, this is not feasible or even balanced, just no.