I just love Scott, and there are way too few fics imho that focus on Scott's feelings, Scott's pain, and Scott's traumas.
For Supernatural my fave character is Dean Winchester by far, and I just love him for trying to be better, putting others before himself, and for all the emotional stuff he tries to hide behind a wall of false bravado. I have a thing for abo in this fandom, because it's a short cut to let Dean be more vulnerable than he'd admit himself to be in the regular universe.
As for Lucifer, while I don't mind ship fic, I'm actually far more interested in the family and friendship bonds on this show. Especially the bond between Lucifer and his older brother Amenadiel.
I love gen fics, fics based around family, found and blood alike, and how friends and family interacts with one another. I love characters sacrificing themselves for others and desperately trying to make things better for those around them, and getting hurt because of it.