The nice thing about Rowen/Rowan is the sound: I think it's a gentle and approachable yet strong name. The sound is unisex, perfect for any gender. I have seen the arguments "it's a boy's name because of the 'Owen' in it" and "it's a girl's name because of Rowena" — both are valid. How you use it is up to *your* personal preference. Don't let some bitter commenters sway you from a good name.
Rowen is also used as a feminine name in modern English. However, it's more common for males. So, I think that the "Gender" of this name should be updated from "Masculine" to "Masculine & Feminine". [noted -ed]