D.S.
Editing my original reply....I have always really liked the name Cass (that could be the full name or short for Cassius or similar). It's not a very common name, and not too weird, and not too trendy. Just kind of unique! Another name might be Cy--I have a second cousin they call Cy...I think it's short for Cyrus.
Additionally....If you want something unique, ask a friend who is a pre-k to 1st grade teacher for what NOT to use...they see the popular trends. I don't really have any suggestions but I can tell you my predictions are that Jax, Jack, Jackson, Cash, Cale, Cole, and Colt will all become quite popular and not so unique (if that is what you are wanting).