I'm not really worried about the number of channels or star power. Although cable/satellite has grown immensely since the Clark shows went off in 1988, there were still some cable regulars back in the day as well (Stuart Pankin of HBO's Not Necessarily the News comes to mind).
And I'm sure you could find a mix of secondary sitcom names and I Love the x0s or Comedy Central Roast commentators/regulars who are capable of giving/receiving clues, yet still just recognizable enough. And going with Chris's point, we could rattle off quite a few celebrities from the 80s version that weren't necessarily big names then or now.
As far as gameplay, I'd prefer to see it remain a half-hour show, mainly because it gives the runner-up from game 1 a second chance if their partner sucks. I also like the idea of four categories instead of six, to allow for a looser structure.
Don't know if this was suggested but if the show runs for an hour, I'd make it more like the 70s network versions, except three matches. Two contestants in the first, another two in the second. The winners of those two games each play a Winner's Circle for $20,000, then face off in a championship third match, with the winner going to a bigger Winner's Circle (say $30,000 to make it a "$50,000 Pyramid"). I don't really care about dollar values right now, and I know this gives the unfair advantage that the 70s version, used. The only other alternative I could think of was do three matches, and make it best of 3, but then you have a pointless third match if there's a sweep.