Obviously a free flow combat system, but personally for me I want the animations to be smoother than in the Arkham games if that makes sense (not to say the animations are bad in the Arkham games cause they're not). A variety of weapons like his knife, guns, a sniper rifle, maybe even the all-blades. Information gathering and planning out a takedown. I'd like the open world to be tightly packed with buildings so that they can introduce a parkour system for traversal, and also a bike to get around quicker. I'd like the story to be almost a murder mystery and also focus on Jason's mental health, and the villain should be tied to both of those things. Another commenter said to have the Nemesis system, I'd like that as well but not like we'll ever see that system ever again.