He's the ideal, and I'm sure it'll happen someday. But right now he's got Hulk, GOTG, cowriting Empyre, and whatever he recently hinted he has coming up with Javier Rodriguez (I'd guess the Masked Raider event book spinning out of Marvel #1000), plus now today's full announcement of We Only Find Them When They're Dead for BOOM. Though at least the latter,
along with looking incredible, means he's no longer exclusive with Marvel.
Hey, Pak's worked for DC since then! Not *much*, but he did that Kamandi issue in 2017.
As a relative Fraction skeptic I'd love to see what he'd do, but I'd be flabbergasted if he had any DC projects in mind beyond Jimmy Olsen.
Lately he's been posting a lot of panels from deep cut Golden/Silver/Bronze Age Superman comics on Twitter that looks like research, but if that's what it seems and he is in fact working on another Superman project, I doubt it would be for the main books.