I still have hope that the missing blank mode on the right of the "super mario 3D world" could be for super mario 64.
Is it unrealistic to hope this when we see what is possible today with Minecraft and dragon quest builder ?
It has to be Super Mario Bros 2. The assets for that are ready to go and there wouldn't need to be too much extra effort put in. Mario 64 would require a whole lot more reimagining to make possible. I'm not ruling it out, especially as DLC, but not at launch. I'm almost positive that they'll announce the Mario Bros 2 tool set to start the E3 Direct just to get things off to a rocking start. It makes sense with the "2" in the title, afterall. And it will be one of the playable demos on the show floor. Obviously I could be wrong, and I don't want to rain on your parade of getting a Mario 64 theme, but I think it would just be jaw dropping to see a return of that forgotten Mario realm.