I have a feeling that if a new Muppet TV series were made they won't make the mistake of introducing so many new characters at once while only a handful of classic characters get plenty of screen time. I felt confident of this even before the Disney buy-out. Sure, Statler and Waldorf: From the Balcony had many new characters (even if most of the "new" characters were recycled obscure puppets) but that wasn't a TV series (and I view it more as a spin-off), but the foreign Muppet TV seems to have included more classic characters and very few new ones, and The Muppets' Kitchen (which is online and shouldn't count) only has one new major (muppet) character.
In the "Ask Jim Lewis Thread" Jim Lewis said that Muppets Tonight was meant more as a "next generation" Muppet show, but I feel like if the show includes "Muppet" or "Muppets" in the title then most fans would expect the classic characters from The Muppet Show to be more prominient. And until "The Muppet Show" came along I'm sure most people didn't associate the Muppet name most with any speciffic Henson creations (as the name had been used to describe any Henson puppet creation by then, and still did in productions with original characters afterwards, only "Muppet" wasn't in the title).
I agree, the classic Muppets should be front and center. Have the main core of Kermit, Piggy, Gonzo, Fozzie, Pepe, Animal, Rizzo, Beaker, Bunsen, Sam, Janice, Bobo, Beau, Big Mean Carl, etc.
But I say we DO need new characters. There needs to be a strong new vibrant lead female co-star, Im thinking Skeeter. Also I'd like to see new monsters, maybe frackles.
Btw, I saw some of the French TV episodes of their "Muppets" show. It wasnt so much the foreign language and culture that threw me off or the fast talking, but just the whole overbright gawdy tacky set, lighting and feel of the show I really did not care for. The puppets looked extremely well crafted, though I just can't include it as an official Muppet production in my view.
It's funny that the one new character they made(Denise), the purple lady, ended up in a Muppets.com skit if I recall.