Oh, ho! All awesome suggestions.
Kirby: Super Star is still easily the best Kirby game ever. Well, it's a few games, really, each providing something a little different. Each of those games' in-game headers would make pretty sweet map headers (I like headers!) and one particular game, The Great Cave Offensive, would be REALLY useful when mapped out and with all its treasures located. This would be so worth it when it's all done.
Secret Of Mana was one of my earliest requests, and one I brought back when we were discussing how to have multiple mappers for games that are big, like this RPG. (The request topic turned into brainstorming for what would soon become the Super Mario Bros. 3 project!) As probably the most loved Mana game to date (still seems to be, by some consensus) and beautiful graphics, this would be hot. Like the Secret Of Evermore maps of Grizzly's.
Super Mario World 2: Yoshi's Island is another great platforming game that deserves to be mapped. I could see how that would be done, just with more Super NES-related mapping challenges.
Zelda II: The Adventure Of Link is a good choice too because I'd like to have every pixel from every Zelda game one day. And it also fits into my dream of having the first Nintendo Power Player's guide, the NES Game Atlas, totally obsoleted. I love the book, but a digital form is best!
I said I was going to make a "Projects" page, didn't I? >_< Especially if we do continue with projects.
I also said I likely won't be as involved in the next project as I tried to be with the first two. In the sense that someone else should lay the groundwork. I'd probably have too much fun making the Kirby: Super Star headers given the chance, though.
The first two projects had deadlines of sorts. Super Mario Bros. 3 by the end of last year, and Mega Man Solid X: Guns Of The Mavericks for April Fools'. We probably don't actually need a deadline for the next project, if that was a concern for anybody.