It looks pretty good, as long as you're ok with the none icons making a few icons unselectable. I didn't realize it just by looking at the words, but it's got very nice organization. I never thought of putting the pokemon that way, and could never figure out how to fit the mario characters into that particular 8 slots. Also, i like how the Metroid, Earthbound, and Fire Emblem series are grouped together, but going out of your way to get ness and lucas beside falcon ruins a bit of the organization. Personally, I would put wario below dk and diddy, as well as put Pikachu above PT (both to preserve series order). Putting all that together, it comes out like this:
I arranged the last two rows 64-Melee-Brawl...and I never really noticed it before, but having Pika, Jiggz, PT, and Lucario in that little 2x2 box there looks kinda cool.
EDIT: also, i realized that with my CSS Base Image, you can change the configuration to 9x4 or 10x5 by centring the pictures on the guides (for 10x5, the end column wont have guidelines, but w/e)