I don´t think is a good or bad thing, but I have this friend, he says that drawing faces is like when you want to draw but you are stressed and you want to relax.
Something like that

I see no issue with it. Some people I suppose that this is all they can manage to the best of ability, and I say draw and keep drawing no matter what it is. from a different view though, if you want to improve as an artist, you need to step outside of your comfort zones and really explore/ experiment/ practice.

Depending on my how much detail they put it into can make a difference. I do face-shots, but not to the extent of limiting my capabilities. I think doing both is best so you can find your strengths and improve on your weaknesses. Had you just do face-shots alone, is quite restricting though.

Unuuuuuuuungh, I am still at that stage. How horrid I be....simper simper....fffffffff/ *wrists*

"I don't have an opinion" oh gosh XD

I don't think it's really "good" or "bad" persay. If the ONLY reason you're ONLY drawing face shots is because you're literally AFRAID to try and draw even so much as a waist up shot then I think it can be a problem. I personally draw face shots now and again to break out of my full body shots routine.

*shrugs*
Different people have skill in different areas.
If someones skill is in head-shots, then why would
anyone have a problem with that?

My specialty is trees.
Is that a bad thing?
Should people make polls about whether or not
i should draw trees, when that is where my talent is?
...
I think not.

But again, that is just my opinion.