I'd say that they should take a cue from the comics and promote Scooter to writer. Or at least a bigger backstage producer type deal. Either way, it only matters if it's that kind of show again. But even though they're an ageless troupe of fictitious characters, being the intern for that long? It's time to give Scooter his due. Especially since he's back.
I don't like the idea of Walter being absent completely from future projects. It's a depressing implication that the character went through all that to be part of the group only to have it pulled away.
I'm not saying he should be a main main character, but he should at least be recurring. Just as long as Andy and Randy and the parody pigs stay the freaking heck away from any future Muppet anything. They're terrible.