Everything said here has been great, and I also felt my stomach jump when I read that Randy's looking to get some more work done on the LEDWIZ's - hooray!
One thing I thought I'd throw out there for you, though, arzoo, is that one of the "compromises" I decided upon when doing mine was that of grouping buttons. By that I mean, I wired up more than one button per ouput on my LEDWIZ. You could do the same to conserve your 32 outputs, but still have dual, or even tri-color LED per button "group".
The drawback to this is then of course the type of animations you can do, though, I strongly feel that 80% of what you're hoping to get out of some sweet animations, can still be accomplished well even with some buttons grouped, so long as you're careful in which ones you group to keep things symmetrical, etc. so that things don't distract the eye when running attract sequences etc.
The other big drawback is that depending on which buttons you group, you might very well loose some of the PowerMAME features of lighting individual buttons properly.
But, what I did to preserve the PowerMAME support and still not exceed my LEDWIZ outputs, was to combine my credit buttons together, my admin buttons, and I combined my P1, P2, P3, P4 buttons with my GGG balltop lit joysticks - (link to blog in case you want to see how mine ended up:
KillerArcadeMachine blog).
Anyways, just thought I'd throw that out there to make sure you were thinking of all the options - though the best setup of course will be to have every button independently controlled and capable of a full RGB LED setup - though I figure I'll need 4 LEDWIZ's to do that on my CP, so, like I said, I made some compromises.
