Batman: Return to Arkham Extra Content

With Return to Arkham being delayed indefinitely merely a week from going gold, or being completely finished the game. My speculation of this, is that the frame rate issues are holding them back, but they are also adding extra content that wasn't in the GOTY editions of Arkham Asylum or City. Skins, extra side missions, seem likely here. But maybe a multiplayer mode?

Now over the course of Rocksteady's Batman games never before have they done a multiplayer, WB Montreal's Arkham Origins may have been the first to try this in the Arkham series, but that didn't go well, now did it? This doesn't seem too likely since Rocksteady has always said that Batman is a single player game experience, and this remaster is for the Rocksteady games. But maybe a Co-Op Batman and Robin story mission, this would get everybody to get Return to Arkham. No matter what they do with the extra content, I am super excited for Return to Arkham, it is my most anticipated game right now.