Kurt Russell as Commish Jim Gordon in a cameo would be great to see!
Maybe we see a quick surprise cameo rooftop scene between Bats and Gordon. Can you imagine seeing the fan reaction in the theater with a scene like say....the CC footage, but altered:
The scene:
B goes up to the rooftop and turns on the signal in preparation for the battle with S in Gotham.
The signal is on and while B looks up at the sky....you hear a voice from behind B saying "I always knew you had a screw loose....but I never thought you were this crazy".
B turns and in from the shadows Kurt Russell as Jim Gordon steps in smoking a pipe (a homage)
Movie audience would go nuts!
B than says "It's something that needs to be done Jim"
Maybe they have small dialogue....and then all of a sudden from the sky you hear Cavill as S say..."Good evening Commissioner Gordon".
Russell's Gordon looks up at S floating down slowly from the signal and says in that classic Russell as Gordon voice in astonishment..."Well I'll be....damned".
Gordon than says to B...."try not to get yourself killed".
Then Gordon looks to S and says basically to both of them...."and don't leave a mess in my city"....and then Gordon walks away back to into GCPD HQ's.
A quick scene like that would be just be utterly...EPIC IMO!