Nightwing

Nightwing would also work as a Netflix shows, especially if no Batman is involved. So maybe the former Robin's story should be picked as soon as he left his mentor and went to make a name for himself.

Whether the city is Blüdhaven or some other one, it doesn't really matter. What matters is that Nightwing can be paired (so to speak) with Red Hood and have them finally clash in an epic spin-off. And no, we don't want them to become buddies afterwards.