I like a lot of the tropes people have already shared.
Especially for romance plotlines, I really enjoy it when you have a guy that you think is the stereotypical "hot, male, jerkface" who treats women like objects but is in reality, this warm, sensitive cuddlebear who treats his love interest and all women he interacts with as queens.
I also really enjoy the "best friends to lovers" trope. Enemies to lovers is great, but there is something about two characters who have been together through hell and back and just want to be together. Like the future is scary, but I can face it with you by my side.