Two things I’d love to see:

1) High fantasy au where Hanbin is a priest/prophet confined to his deity’s temple, and Gyuvin one of the guards assigned to watching over him (and making sure he doesn’t escape). Gyuvin starting out as a devote believer of his divinity until falling in love with Hanbin makes him question his faith (and his role in basically keeping Hanbin prisoner).
Bonus points if one or both of them have celibacy vows because of their roles.

2) More canon compliant fics, especially something about their jeju trip or shenanigans from their new living arrangements, I’m very curious to see people’s take on their relationship (when it started, how it developed etc, how it fits in the group dynamic etc)