Like a lot of people in this thread, I consistently write main characters of one specific gender. That's actually what helped me figure out I was trans—my strong preference for male main characters. I love writing women, but my main character is almost always going to be a man.
I have an unfortunate drive to make things not work out in the end. I love making things go wrong and wrong and wrong... and then I struggle to figure out how to pull it back for a happy ending. So a lot of the time, there just is no happy ending.
That said, I also struggle to not insert inappropriate humor in everything I write. Things are gonna be at least 35% silly all the time.
I insert my interest in real-life cultures and languages into my writing, so you can expect a lot of real-world languages and aspects of culture popping up in my fantasy settings. I love Slavic naming systems so much that I have used them in multiple stories and settings.
My main characters are also almost always some kind of rebel or criminal or otherwise alienated from mainstream society.
Oh and gay! My main characters are always some kind of gay.