If iD games stopped trying to take themselves so seriously and they did a technologically superb Painkiller a-like with all the features people love like drop in/out co-op, online leaderboards and some sort of objective based multiplayer (anything where good tactics would help a bit to negate a lack of twitch skills) it would be win win win all the way to the bank. They know good fast paced core shooting mechanics and their obviously talented artists could go nuts designing differently themed levels.
Seems like Croteam is making the games that iD should be making. Both in terms of gameplay and technology.