i think about kessler(INfamous),zoran lassarevic or eddy raja(uncharted),DR.Nefarious(ratchet and clank),neo cortex(crash bandicoot),the boss or big boss(mgs),big sister(bioshock),zeus or hades(GOW),calipso(twisted metal),polygon man,¿the sing of anonymous?
Well hades can't be in it because he's part of an arena but all the other ones are great picks. I'm dying for Dr. Nefarious, Barron Praxis, and Kessler to be in this game. And as for Calypso, he should be the final boss. He organized the Twisted Medal games so maybe he could be the one organizing the fights in PSASBR.