Kind-of Anticipating: God of War: Ascension, Metal Gear Rising: Revengeance, Aliens: Colonial Marines
The reasons may be that:
A) They already had Radec. They would have too similar of a playstyle for this roster initially
B) Insomniac may have wanted to take a step back from resisitance for a little while. It wasnt a bad franchise, by any means, but the games did just finish, and they may have felt that it wasnt important for that franchise to be represented right now.