Lyvidian: I think the height and weight is really important, even for OFCs. I mean, if you say "he reached up to the top shelf" but later tell your readers that the character is short... that presents a problem.
Another thing I like to do when I'm stuck on character looks:
TekTek. It may sound strange, but I often think of my best cultures and characters while I'm tektekking. I will give this warning: TekTek has a tendency to produce plot bunnies. Like, it probably gives me a plot bunny for every decent idea. And sometimes it just gives me duds. But when I get it right, it at least gives me a general reminder of what my character should sort of look like (eye color, hair color, typical garb).
Also sketching characters, scanning them in, and adding the profile as text on the image.