I think Clifford represents the turning point of Muppet confusion when it really should be someone more like (dare I say it) Digit. I love that character, but he's the one in the Henson Hour that took the honored place reserved by Bunsen and Beaker. I feel that's why the character hasn't returned. Writers would rather come up with material for the crowd-pleasing duo than try to sell a largely unknown character.
I think I used to think of him as being similar to Bunsen, but he is also different from them. Bunsen and Beaker are scientists, and Digit was a robot, and a technician. If Dave Goelz didn't perfirn Digit then maybe he could have teamed up with Bunsen and Beaker on occassion, without it seeming like he replaced either.
Now that I think of it, while Solid Foam replaced The Electric Mayhem, did any members seem like direct replacements of the Electric Mayhem members who played their instruments? Digit played the keyboard but as far as I know wasn't the leader (did the band have a specific leader?), and while he has a really cool design, he looks a bit square compared to Dr. Teeth (is there such a thing as a hip square? Or a square hipster? Because I think that could describe Digit). Flash was a singer, while Zoot didn't talk much. The drummer wasn't like Animal, rarely even speaking. I think Clifford is a bit like Floyd when he's not a host, and I feel the same way about Leon (what, did Kevin Clash's contract state that he needed his characters to be like Floyd?), and I guess thatmember would be the most like the Electric Mayhem member of the shame instrument. I'm not too sure of what Beard's personality was like, so I'm not too sure if he can be compared to Janice, personality-wise. He looks very similar to Zeke from the jugband (who looked a lot like Lips from the Electric Mayhem, and Solid Foam didn't have any trumpet players).
But somebody with more access to The Jim Henson Hour will have to confirm that I'm right or wrong. I don't know if the shows production order was the same as it's broadcast order (and I'm mainly referring to the MuppeTelevision segments here... I know that all of The StoryTeller episodes had been completed by then), but the last broadcast episode featured Animal in place of the drummer, and Zoot in place of Flash. I wodner if Jim Henson had decided to get more known characters on the show, and did this in an attempt. We may never know, as there weren't any more episodes (but it would be weird if the band had intended to change that way, because then Dave Goelz would have had two musicians in the same band).