I would be interested to see/hear what you come up with for this. I have been thinking of trying an old school 60s airstrip drag track diorama. Sort of an illegal street racing scene I can drop period cars in for pics.
I have collected many reference pictures but haven't been able to find anyone who has done something like that. I'm sure it's been done, it's not that original but I still can't find anyone who has detailed or made a tutorial of it. Experimenting seems the route I'm gonna have to take. I've never done a diorama before so a simple dusty tarmac is a good a place as any to start.
Also, just a thought. The bat-mobile with LED street lights casting shadows all over it would look pretty awesome as a diorama. You might even be able to rig up a bat symbol cast in light on the street or something slick like that. There is a lot of potential for a batman dio. Good luck and keep us posted.
Gordy