I'd love for Khalid to get to be an actual character again. He's stuck in the same role that writers always seem to stick Doctor Fate - regardless of which Doctor Fate it is - in: bland mystical cameo character. It's the same thing that happened with Kent. Seriously, it's the exact same thing: they're being written the exact same way.
The Doctor Fate tie-in for the Black Adam movie was decent and left me hopeful they might use some of his lore.
God, I'd love for Doctor Fate to get a mini-series in the wake of the movie with Kent in the role and Khalid as his grandson/apprentice. It'd be a good way to re-introduce Doctor Fate lore and give the character some memorable chaos villains. Kent's story would be great to set the tone and nature of the grey-and-grey conflict between order and chaos because he was a victim of order, but has also fought against chaos and is basically trying to be the good in that grey-and-grey conflict. His backstory works well to introduce the cosmic horror aspect and his relationship to Nabu is just dark psychological intrigue incarnate when writers explore just how screwed-up it is (Never cared for the creepy Linda-and-Eric thing, but I absolutely loved the Kent and Nabu parts of the Dr. Fate mini-series)
Including Khalid as his immediate supporting cast also means you have someone who is new to all this horror, it gives a chance to better establish Khalid's characterization and his relationship to Kent would be a good way to have some levity and sunshine balance the darker aspects. Khalid and Kent's relationship was one of my favorite things in the Justice League: Dark series and I would love to see it return. I liked that Khalid had a different approach to handling Nabu because he never went through the same things as Kent did. It was a nice contrast that added something and it made a lot of sense because Khalid was never "raised" by Nabu.
For example, he was a different kind of defiant and had a way of getting through to Nabu (and other gods) by knowing how to appeal to their way of thinking and not through verbal appeasement. His exchanges with Nabu were always interesting to me.
It was a good dynamic so, naturally, Nabu died with Kent because god forbid, Khalid has any interesting supporting cast to interact. I was really sad when JLD got cancelled, but to be honest, I've become less sad about it over time because Khalid was basically losing everything Doctor Fate-related: he'd lost Kent, he'd lost Nabu and he was about to lose the Tower. The way they handled his grief over losing Kent - namely, the fact that they didn't handled it at all save a single exchange between him and Bobo - didn't make me confident they were actually going to build him back up.