Every story has its own unique needs in order for them to be told the way I want them to touch the reader. To me, the first person point of view is a bit less of telling a story from the narrator’s perspective, and a bit more of making the reader feel as if they're the main character.

For romance, when I'm telling the story of a couple, it seems wrong to "make" the reader the protagonist; instead, I want them to be a spectator, seeing the way love blooms between two people, I want readers to be witnesses to that love story. I want them to see that love story and covet for themselves, to spot the red flags and fine-tune the characteristics they wanting a partner in the same way we do when listening to a friend talk about their relationship.

I don't exclusively write romance in third person. Silly Season, which is the book Thea Scriven had been working on in Ellipsis, is written in first person & in dual POV, but that's because I want to differentiate my writing from Thea's.

TL; DR

When I write in third person point of view, I want the reader to experience the story as a spectator and not as an active member of the story in the same way first person can make them feel that way.