So for a spin on the battle city thing, Where Ante would be a thing, and the whole place is prone to being a complete shithole when it comes to later things.

Why not just run it in satellite. What with the duel gangs, and the fact that making a deck usually involves scavaging the shit out of it (A canon way to not result in super high tier decks) While also the fact that trading would be seen as incredibly generous and mean something. 

some individuals could certainly be from New Domino/other parts of the world, thus different motives.

What I'm saying is

New Domino + Satellite offers a better locational environment then say just battle city. PLUS Police duelists.