I think Jen tends to play it safe, hence her dress choices are usually pretty boring. She'd rather lay it safe (and get put on the best dressed list) then risk being individual on the red carpet.
She often said she hid behind her hair and I think that's very true.
I think she's pretty but no stunningly attractive. I always thought she had a very weird jawline. I think she benefits from good lighting, make-up and wearing designer clothes. Other than that, she really wouldn't stand out. Saying that, I always got the sense that she was very nice, down to earth and didn't take herself too seriously so I give her major points for that.