Like Mario sunshine. But the hub world itself is a big ass level (GTA sized) with hidden stars and places that require power ups to reach.

And here and there, there's a unique level with a door ala Mario 64, but the core itself would be the open World.

You could have Yoshi or the Tanuki Suit acting as transportation, equivalent to GTA cars and planes. Not to talk about the sewers which could act as highways.

And I think the "Universe" word is an obvious use with the Wii U but it suits better the Smash Bros series.

It's funny though because most Mario Galaxy levels are actually more like the Bowser level you showed from Mario 64, while the most Mario 64 levels are more like the Honeycomb level you showed from Galaxy!

I'd still be quite interested, even if it were Mario Galaxy 3. A new motif wouldn't go amiss, but there's still probably a lot of life left in the Galaxy design.

I'm not sure they'd go for it, though. New console is the best place to start afresh with something like this (i.e. Sunshine; Galaxy 1)

Won't games with such a co-op feature look... bad?
'Cos, I mean, the WiiU would have to render the same stuff twice, one for each screen, so the game will only look half as good as a single player game on a single screen would?
I dunno, I'm not a tech guy, but that would seem logical to me.

3D Mario is gonna be so awesome on Wii U.

They need to focus on making the game harder.

A lot of the time it was just basically "follow this carved out path and watch our pretty artwork"

It sounds like you haven't played Mario Galaxy 2 at all.

I just did the other day.

The final bonus levels were nice. But after not playing for about a year I picked it up and beat them after a few tries

Sounds like you didn't play Galaxy 1, because G1 demonstrated free roaming much better than 2.

??? I never said it didn't