Obviously by now its apparent that, there will be four first DLC characters. I'm gonna go out on a limb and say Kat and Emmett 'aren't rivals'.
This leads up to some possibility.
To keep this simple, don't just suggest someone like Crash and say 'lol becuz crash' (unless you're trolling in which case trololol), bring some actual intelligent thought in here.
Kat's rival will either be King of the Cosmos from Katamari, or Lil and Laarg from Escape Plan. I'm actually hoping; no, expecting King of the Cosmos to be the DLC character, and have the Escape Plan be an entire stage mixed up with, say, Heksville.
For Emmett things get a bit crazy, but I'm going to assume either Joel from The Last Of Us, or that new kid from Beyond: Two Souls. I'd say Resistence's Nathan Hale but Resistence already has quite a lot in the game being the only non-character-represented thing with unlockables and items. (Buzz!, LocoRoco, and Patapon don't have anything.)
Did I miss something that hinted at a 4 release?
Anyway, I agree with Kat vs. the King. I'm not sure who I'd want paired with Emmett, I really don't have any other DLC desires in mind that aren't a cookie cutter Crash-like pick that would be a good fit for Emmett.
I'm not familiar with any of the games you suggested as rivals for Kat, but Nathan Hale and Emmett Graves are perfect rivals. SuperBot would be silly not to take advantage of that.
Patches the Hyena (Dark/Demon's Souls) for All-Stars! His level three could have the player leave the match, enter a random match, and get one-hit-one-kill's on everybody! xD
Hasn't Seth commented on King of the Cosmos several times now?
He has. I think they kept him post-release so they could figure out how to fix some of his moveset. Considering he's like, 'the' best pick for Kat's rival (Gravity Queen vs King of the Cosmos, Dusty having a space-like texture), it'd make sense to pair him and add him with the new set.
I agree with you Marrow, I believe that there will be two other characters released with Kat and Emmett.
I have this strong feeling that Dart will be Emmett's rival. Every since Seth hinted that Emmett and Kat won't be rivals I have had this feeling that Dart will be Emmett's rival.
As for Kat's rival, i'm not sure. A Lil and Laarge would make great sense to have two Vita rivals.
Emmett Graves vs Nathan Hale need to happen. If the King doesn't make it then Kat can rival with Ellen from Folklore. What I would love to see is Kat vs Kit from Blade Kitten. I think blade kitten need to be in this.
^^they never said they were rivals but the problem is... that means there are FOUR characterless not 2.. and there are 2..
Two that we know of. Do the math:
2 characters that are not rivals
+ both characters have to have rival scenes for Arcade Mode upon their release