[Gnome]

Can you post an example with a specific college, points spent, and consequent abilities of the character? I'm confused by what you mean here, and I think it's because of your use of the word "wildcard" to mean something different from what I'm used to.
Are you using "wildcard" as a kind of Unusual Background that allows a character to learn spells from the college? Do I still have to spend points on those spells? Is this just forcing me to invest heavily in a particular college before I can learn its spells (and isn't that what the standard prerequisite system is supposed to do anyway?)?
I think I see the problem you're trying to solve (although to me the fact that you can build both generalists and specialists in Magic seems like a pro, not a con), I just don't see how your system solves it, since I don't actually understand what you're saying due to peculiar use of the word "wildcard."