I honestly love Valen. :) I had a friend several years ago who had a son named Valen, I remember thinking it was one cool name! I also like Vale/Vail for a boy, though, too. I can't really see Valen on a girl because of her son, but strangely enough, I sort of like Valens for a girl. Or you could do something like Valentina, which marks it firmly in the feminine camp, and use the nn Valen/Valens?