A few things I've noticed about paranormal romance tropes after reading too much of it:
When the hero says "mine" in paranormal romance, it's doing something very specific. It's possession framed as protection. Readers want to feel claimed, not controlled, and that distinction is harder to write than it sounds.
In J.R. Ward's Black Dagger Brotherhood, the brothers all have trauma as the baseline of their existence. They weren't born warriors; they were remade by loss. This is the architecture behind almost every successful paranormal hero: the supernatural state as aftermath.
The hero who can scent the heroine's fear and desire, who tracks her presence from a room away, is giving readers a fantasy of being unmistakably wanted. Being too legible to someone, being seen through, is frightening in real life. In paranormal romance it's the point.
Finding each other 200 years later is a specific fantasy: that some loves are so real the universe keeps trying. Time as proof rather than enemy.
Most paranormal heroines have a supernatural ability they don't know about. When readers roll their eyes at this, the trope almost always holds up. What fails is the execution, the power arriving exactly when needed, twice, without earning its place in the story.
What makes the alpha paranormal hero worth reading is restraint. He could override her. He doesn't. That choice, made repeatedly, is the thing that earns the reader's trust.
Forbidden between species has a different weight than forbidden because of circumstances. When the structure of the world says this pairing shouldn't exist, overcoming that is a different kind of win than overcoming social disapproval. The stakes are ontological, not just social.
I'm still not sure how Kresley Cole built such a large paranormal universe in Immortals After Dark without it feeling like the reader needs a guidebook. Each book introduces enough of the mythology to work on its own while rewarding readers who've been there from the start. I know how that works technically, but I don't know why it feels so effortless when so many similar series feel like homework.