What they should do is make a modern version of the show, sticking with the original format and not screwing up like they did with Muppets Tonight! Of course it should include the classic opening, just like they did in the new movie!
When Muppets Tonight was good, it was VERY good, when it was bad, it was very bad. There are some skits that genuinely worked, and usually those were the one shot parody skits like Seinfeld Babies and Co-Dependance day or even the UK bits like Fairy Tale PD, Mr. Calahan, Swift Wits, and Boarshead Revisited. it's such a shame the Uk segments were better than the pig segments (Deep Dish 9 and Bay of Pigs Watch).
Substantially, the show was MUCH better second season, late second season when they took the action outside of the theater. The Andie McDowal episode where Bunsen is separated from Beaker (on a Star Trek cruse, being harassed by George Takei) is actually quite brilliantly done as was the Johnny leaves Home episode.
Still, I want something that utilizes the classic Muppet Show theater, but doesn't slavishly copy The Muppet Show. I want to see Pigs in Space with the classic cast, and Muppet Labs and the Swedish Chef are all too much a staple to change... but I want some sort of new segment. There was a brilliant comic where Robin was trying to explain stamp collecting while Sweetums was busy munching on his collection... I'd LOVE to see a Robin and Sweetums segment like that.
In the meantime, sure... rerun the thin on Hub. At least then we'd see season 4 and 5.