I don't really think of her as having a manly face--she just looks that way. ^^
For example, not all women have narrow eyebrows, and Lin's one of them. (In my gallery under "Jerry's" [link] you'll see that her brother has thick eyebrows too, but his are bigger).
Lin has a flat chin, as opposed to a pointed chin, but it's really my fault that it looks big. The same goes for her nose. These were more because I wasn't paying attention when I was doing the outline. (I was in class). Those two features came out more exaggerated than they should have been.
That's about it, really. Thank you for your thoughtful comments, I appreciate it.