Hannah is very nice. It's been overly used for the last couple of decades, though. But if you don't mind that, then add away.
Hannah always makes me think of a simple, kind, hard-working country girl. It has "salt of the earth" written all over it.
I still suggest it as a mn sometimes. I like to use mega-popular names like
Hannah or
Emily or
Emma as mns. People don't expect it.