I was actually thinking they may be heading in that direction with this game. I mean with all the microtransactions that seem to be coming into place it actually reminds me of UC3 but I don't think I've ever seen the model on a fighting game before.
They'd either need to release a bare-bones downloadable version with only a few levels and characters (no single player, maybe?) or release a few more characters in order to make that work. The bare-bones roster would be interesting to see, as they'd then become what flood online matches (it'd be neat to see some less-popular characters make that batch). Fat Princess, PaRappa, Jak, Toro, Spike, etc.