Woah! Now that’s something to think about.
I’m with you on the whole niche debacle. Coming into the writing world, all you hear is “pick a niche!” It’s like the first rule actually.
That said, I still don’t have one.
However, a year out, I do know what I like to write about. And I know what topics / concepts people like to read — that’s part of the exploring you mentioned.
I agree it’s better to wait.