Catlin could be cool. I know a guy who goes by Cat.
I just have a really hard time rationalizing a difference between "boy names on girls" and "girl names on boys," other than that the former is a trend we're use to seeing. I'm no staunch advocate for keeping names forever gendered I just wish there weren't such a double standard, or at least wish it swang the other way. There seem to be SO many great girl names out there (what feels like more than boys), so the whole trend just doesn't seem logical to me.
....and I'm someone who loves
Vaughn,
Reed, and
Joel on girls and
Whitney,
Mayim, and Somer on boys...