Most Underused Muppets?

[FunnyBear]

Kermit the Frog
But for real, we should see more Gonzo and Rowlf.

 

[Muppet Master]

I think Vendaface was EXTREMELY underused, and if they count as muppets, the moopets, which besides Miss Poogy, we'll probably never see again!

Moosehead
The Moosehead hasn't been seen since Muppets from Space.

I know, that guy could have been someone, he was only in MTI and MFS briefly!