Getting back to the topic again, I'm very hesitant about having SM64DS-style unlockable characters. At least 70% of the fun of SM64 came from the complete freedom it offered, and for me, SM64DS completely took that away by splitting up abilities among 4 characters that have to be switched between. Even when all the levels have hats, you still can't just go around as Yoshi the whole time - what if you want to do a wall kick in the castle? Then you have to walk over to the Secret Slide room, walk through the character door, and walk back to where you were. No spontaneity.
If it was like Galaxy, where the optional unlockable character gives a different playing experience but can still do everything, I'd be all for that. Although I might want a more different playing experience if I had to get 120 stars again for each character.