Exploring other genres when you write
I read fantasy and sci-fi in about equal amounts, and I occasionally like me some historical fiction (which I found via Alternate History.) The elements I love - world-building, dynamic characters, action, suspense - exist in all three of those places.
As for romance, humor, mystery - I think any good story has elements of those. And poetry is super useful in fantasy. Having someone sing a ballad about the war that was fought a hundred years ago is way more fun than droning on like a history textbook.
When I was younger, I wrote everything (badly, mostly, but I wrote it!) Poetry, drama, fiction, nonfiction--and in fiction, every kind of fiction I was reading. I still write verse (almost no serious poetry anymore--I wasn't that good at it) and haven't written a play in years. I still write nonfiction, SF, fantasy, and occasional weird stuff that's hard to classify. I sold a mystery story once.
I think the writing--all of it--contributed to my toolkit, gave me specific skills I still find useful in what I write the most. So did the broad reading, which I started early and have continued...I never read just one kind of thing. (Well, that's not entirely true. As a young reader, say ages 6-8, I read mostly horse and dog books. But I started reading other things at about age 8, and that increased with the years.)