Yeah, the structure and thought behind this proposal all looks quite sound to me but I've only one thing I need clarification on:
So when you say 'x' Firepower point represents the amount donated, does that mean something like this?:

1 = $1
2 = $2
So on up to 10 = $10?

or,

1 = $10
2 = $20
So on up to 10 = $100?

You know what I mean?
Also, is there a cap on the maximum amount donatable?

Other than that, I'm all for having this implemented!
Perhaps a Poll may be useful too Griffin? - Just odd that more members haven't posted their thoughts IMO.