On top of Marvel's anti-Fox regime outside of the comics (mainly with Marvel refusing to give the X-Men or the Fantastic Four appearances games, cartoons, or merchandise), Activision's contract with Marvel was revoked outside of the Spider-Man deal which was made with Sony before Marvel took up the merchandising rights to Spider-Man (which I think ends in 2017). Until Marvel gets the mutant rights back for the movies, we'll never see another Deadpool-centric game...or any mutant-centric game. And even if we did, it wouldn't be under Activision & High Moon Studios.
The only things we'll ever get are either Avengers, Guardians, Inhumans, all of the MCU, or all of Marvel minus the characters Fox owns the movie rights to (which is basically the MCU plus a few who haven't made it into the MCU, yet).