This looks fun. You don't have a lot of level designers, as I can see. I dunno if I'd have time, though. School is coming up pretty fast, and I am currently working on The Mushroom Kingdom Catastrophe, so I am not sure about joining. I'll consider helping, but i'll have to think about it.
UPDATE!
The game will have 9 levels before the pyramid. Each one will be SMB1 styled. Once you get inside the pyramid, the level design will get spruced up to include many themes, including Beehives, Deserts, Candy Lands, Caves, Ruins, Forests, Jungles, Beaches, and more!
The hub is supposed to look like a pyramid, the level themes won't have any impact on the hub itself. Just make 6-7 doors on each floor, and a separate secion for the bosses (which will occur both inside and outside the pyramid).
UPDATE: This is on hiatus right now. I want to work on another project for a while. Don't lock it, I will still accept team requests, I just want everyone to know I'm not currently working on this.