I think Treasure Island is a complete improvement over MCC. I do like MCC, but it seems the Muppet part of that is mostly window dressing. I really like Gonzo and Rizzo as narrators (though the guy who wrote the comic book Muppet Snow White did an even better job), and Kermit and Piggy's portions were sweet, it just lacks something during longer periods. Fozziewig's Rubber Chicken factory would have been a nice touch. But they were just mentioned in passing. Seems to me, they could have just used the creature shop and made a straightforward adaption and it would have been roughly the same effect.
Now, MTI manages to be very Muppety, even though it's carried by the newer pirate characters. The songs are wackier, the gags are far closer to the Muppets (especially the tourist rats), and over all, it feels more like a Muppet movie. Still think they should have got someone else to play Jim Hawkins... but you can't hate Tim Curry. He needs to work with the Muppets far more often.
Now, MTI manages to be very Muppety, even though it's carried by the newer pirate characters. The songs are wackier, the gags are far closer to the Muppets (especially the tourist rats), and over all, it feels more like a Muppet movie. Still think they should have got someone else to play Jim Hawkins... but you can't hate Tim Curry. He needs to work with the Muppets far more often.