I did a bunch of walls for my prospective AGGRO battles. It seems to me there should be some narrow alleyways and places like that. I did some graffiti for them. Not sure we really got tightly themed and colour coordinated graffiti like this irl.
I also finished a little turnstile block for the stadium. I didn't bother doing the interior coz the 20mm bases wouldn't actually fit through scale turnstiles.