Both could be of interest if they were made realistically
How would you do both realistically? Genuinely curious.
Writing believable characters/romances is at the same time very easy and very hard.
On the easy end, take a few basic fiction writing classes and drop all your personal beliefs and biases at the door. Writing is an act of creation, and the writer must create something different from themselves.
This same principle is why writing characters can be very hard, because a lot of writers are opposed to creating characters not only very different in personality, but also diametrically opposed to their beliefs.
Romance is just an extension of your characters. But I think this is a hard one because I don't think most modern writers have any conception of what a normal relationship is outside of movies.
TL;DR: Take some writing classes taught by people who know what they're talking about. Read lots of books. Get more life experience. Have more sex, it's good for you.