Duke presents a problem for the DC writers. It’s 2016, DC’s launching Rebirth, and you’ve got this character who has taken up the Robin mantle in a different way. If you don’t tie Duke to the Batfamily, he disappears. DC isn’t interested in preserving him as his own thing (which would have been the most narratively satisfying thing for him). Instead, he gets put into the Batman and All Star Batman titles. But as soon as you put him into those titles, you’ve lost what makes him unique. You’re left with yet another smart, dedicated kid who wants to do what’s best for Gotham and is going to pursue that by working with Batman. He’s got a different name and costume, sure, but he’s essentially fulfilling the same role as, for example, Tim Drake’s Robin.
The Cursed Wheel, the backup story for the first arc of ASB, is directly about how Duke fits into the Batfam and what his role will be. That’s written by Snyder, who created Duke in the Batman: Zero Year story, and who I think is really interested in moving the character forward and keeping him around. Ultimately, DC (whether that’s Snyder or Tony Patrick or someone else) lands on something that, from a publishing perspective, makes sense, which is giving Duke powers. That’s an easy point of differentiation that opens up new possibilities. They also go with a daytime vigilante angle that’s a little silly (IMO) but works well thematically.
But they haven’t actually solved the problem. They haven’t given Duke a story or character trait or role that successfully differentiates him. And part of the problem goes back to my initial point — what made him unique (his disconnect from the Batfamily) was also what made him (in DC’s opinion) totally unmarketable. They didn’t want to pursue a genuinely new story because the entire comic book industry is kept alive by simply writing the same story over and over again. Another part of the problem, though, is lack of follow-through. They made Duke the daytime vigilante with light-based powers, didn’t give him a solo, and have shuffled him around various books. Rebirth was a decade ago! By the time Tim Drake was ten years into existence, we were on issue 60 of his solo series.
To sum up, I’m not saying Duke hasn’t had good writing. I’m saying that DC doesn’t seem to have a good vision for the character, and every time someone does have a good vision for the character, DC changes direction. We’re left trying to assemble a character out of short stories, which is never going to let Duke be a character as well-defined as Cass or Damian or Dick or any of the others.