So, I would recommend:
?Jak, Daxter, Ratchet, Clank, Sly and one of Sly's sidekicks. Sure, they were all already in Heroes on the Move (It will never be Playstation Move Heroes for me; that's a dumb name!), but they're classics and iconic. You just can't have a game like that without them.
?Nathan Drake
?Cole McGrath
?Kratos
?Sweet Tooth
?Old Snake (In your face, SSBB!)
?Sackboy
?Parappa the Rapper. Or even better! Lammy from Um Jammer Lammy! Who else liked the game?! ...No one? Just me..? Haven't even heard of it...? *Sigh*
?Someone from Tekken
?A Helghast (Bonus character?)
And the harder-to-get-but-glob-that-would-be-awesome characters:
?Crash Bandicoot. Because he was originally Sony's pet.
?Spyro. For similar reasons as the one above.
?Dante. Again, similar reasons. And he's badass.
?Someone from FF7, FF8, FF9, FF10, or FF12. Because they're still PS exclusives for the most part (I know about the PC versions, yes)
?Pyramid Head. Because people would literally throw their wallets at you if you did this. Thus, SH was, yes, you guessed it, a PS exclusive at some point.
?Someone from Kingdom Hearts. Same reason as Pyramid Head's one. And not only would they throw their wallets at you, they would throw their underwear and their wives at you too.