Often times begining writers write alot of stories in alot of genres before settling on one that they feel is right for them. While it may not be my favorite exercise, the creative writing assignment that forces you to think outside of your genre box is good for you as a writer. You might find that you write one style really well inspite of your preconcieved notions.
My first love as a young reader was Science Fiction. That was what I chose to write as a teen. Well 20 something years later I write technical suspense not sci/fi like I thought I would be writing. I don't write the science well but I have found I am good at character based thriller plotting style. And, even if I can't write a full on romance, I have romantic themes in my stories.
Funny story, my friend and I were talking and she had assumed that I wrote romance until I was telling her what "my assassin" had done in the most recent chapter.
Well, 7 years into writing seriously I have not only found a genre I love, Tech Suspense, (add a little Urban Fantasy here or there) but I have found a "theme" in my writing. As my logline says I write about "bad boys (or girls) that go good". My characters go through events in the MS that change them and their lives. I like the process of deconstruction I take them through to get them to a better place.
As of now I have 5 serious ideas or rough drafts about some bad boy or another and what happens to then as they change to being good. Granted, two of those ideas have a paranormal urban fantasy leaning, and I have a YA that while the character isn't a bad boy, he goes from being an immature teen to a responsible young adult. Obviously I have a pattern that works for me.
It's a nice feeling.