What do you want to see in Arkham Asylum II?
I would love to see a coop story mode with Batman and Robin and/or Nightwing.
Just imagine one at either end of the room taking guys out all over the place. I know I'd s**t myself if i was a bad guy.
A decent new game +
If you could go to the normal batcave and Bruce Wayne's mansion
"That house was on fire when I got here,"
-Maybe instead of Oracle it could be Alfred
-Use of the Batmobile in Gotham
-Being able to customize your suit
-More grapple options
Much more takedowns. Like if you're in front of a guy, you can take him out. The takedown would be something like, Batman kicks thug in stomach, jumps over his back, and then does a silent takedown. That would be cool. And also, maybe if you tap Y and a different direction on the analog stick, you would do a different takedown? Just tapping Y would do a standard silent takedown. Y and right would have Batman do that thing where you chop the person on the shoulder and they fall back (I don't know if that really works). Y and left would have Batman violently turn the thug around, thug flinches, Batman punches in face. You get the point - more variety.
Also, I would like to move unconsious thugs. You can let set them somewhere where it attracts his buddies, then jump down and beat them all up or something. And no suicide collars, please.