To change the subject, or rather, return to the subject. Here's some examples of some portraits done by a Japanese photographer, some using 50mm and some with an 85mm. I've tried to find just one good one done with his 12-24mm, but I can't find it. But I agree with the others, the 70-200 range is generally better.
I wish I was able to submit some comparison pictures here, comparing my two favorite 35mm lenses (55mm f/2 Pentax and 100mm f/2.8 Pentax). I may pursue this today, as I'm taking the camera out on a road trip with my family. If I get something comparable, I'll post it here.
But my feeling is that while the 55mm certainly can be used to advantage the 100mm (close enough to 85) flattens the perspective to better appreciate facial features, and they do look slightly more natural. This 'natural' look may not always be what we're looking for, though, and only creativity stands in the way of using any lens. I've seen some extreme wide angle pinhole portraits that are just fabulous.
"Often moments come looking for us". - Robert Frank
"Make good art!" - Neil Gaiman
"...the heart and mind are the true lens of the camera". - Yousuf Karsh