I like most of the popular choices; Snake, Crash, Cloud, and Spyro are all awesome characters that could have great movesets. Ico and Wander are probably the only ones I'm really against getting in. I just think the game is made in a way that those two really, really wouldn't fit in. Stage or item representation would be much better for those 2 IMO.
Tomba. Didn't like his game. I'm also torn about whether or not I'd want Wander. I loved Shadow of the Colossus, but I don't think he'd make for a good character, since all he does is swing his sword, climb on monsters, stab, and shoot arrows. I guess you could include the colossi into his moveset, but that would kind of ruin the magic of them because they felt like they were actually huge in that game.