Great character and I love what Simone did with him in Villains United and Secret Six.
I’d love to see him back in Gotham for a bit and still as an outsider to the heroes and villains. I think there could be some gold found in him interacting between the different characters. A good amount to explore between him and Batman, Catwoman, Nightwing, Batgirl (Barbara) and some of Gotham’s villains.