AFAIK, there's no real "collector scene" for Wizards, so you'll just have to collect whatever you want. If it were me, I'd go for plastics that aren't in production anymore. I'm far from a Wizard history expert, but I'm pretty sure there was a retool after the protos to thicken the flight plate (they warped pretty easy, IIRC) so a proto is probably a good thing to have.
The Chief, while not horrible great or collectible (aka expensive or desirable) is probably worth adding. It's just a Wizard in H plastic. They're cool because the colors are really vivid and neat, the plastic has this cool, rubbery feel and they're super domey. I found they made great approach discs (easy to turn but had a hard fade) but weren't all that great for much else.
Finding an actual "Firm" Wizard might be cool, too. I don't think they mark them that way anymore.
If you want to be silly, there's this run of really slick, firm ones (marked medium) from a few years ago that were considered by many to be one of the worst runs. It's the only Wizard I've had actual trouble putting with because of slickness. The two I had were light blue. The funny thing is they beat in really nice but most never gave them the chance to do that because of how slick they were.
