Considering Game Republic is dead, I don't think we'll be seeing any of their stuff tbh.
Why? Sony owns the Folklore IP for example, so they can do with it as they please.
I'm still hoping for Ellen to show up, although I understand more people want more classic characters.
If I had to choose 4 characters from this generation to represent the PS3, they'd be
Drake (Uncharted)
Nariko (Heavenly Sword)
Ellen (Folklore)
Cole MacGrath (inFAMOUS)
For PS2:
Kratos (God of War)
Jak and Daxter
Sly Cooper
Ratchet and Clank
For PS1:
PaRappa
Alundra
Spike or Specter (Ape Escape)
Sweet Tooth (Twisted Metal)
PSP:
Jeanne D'Arc
Patapon
Gabe Logan (PS1 character, but I think the PSP Syphon Filters really brought the series, and Gabe, into his own)
Loco Roco
PS Vita:
Kat (Gravity Rush)
Lil and Laarg (Escape Plan)
The Blob (Mutant Blobs Attack- although the series originated on PS3)
Juan (Guacamelee)
I think this roster would be my ideal setup, with some third party characters like Cloud, Lara Croft, Crash Bandicoot, Spyro the Dragon, Solid Snake, and Chris or Jill, all in their original designs, for maximum nostalgia. A nice mix of old and new.
Any franchises not represented by a player character would be represented by a stage or a power up.
Hidden, or unlockable characters:
Lazarus Jones (Ghosthunter)
Jennifer Tate (Primal)
Rau or Tati (The Mark of Kri, Rise of the Kasai)
Ari and Stan (Okage: The Shadow King)
Characters like Rose, from Legend of Dragoon, Max and Monica from Dark Cloud 2, Leonard from White Knight Chronicles, Jaster or Kisalla from Rogue Galaxy, would be DLC characters.
I think Superbot is showing a lot more characters from this generation (not including Kratos, Sly, and PaRappa), because they are building hype by showing the more immediately familiar characters to the audience. I think some of us are going to be surprised with who they bring out of the vault for this game. At least, I hope so...