Hi Brian,
I am no good at self portraits, so my opinions should be taken with a a grain of salt.
for the focus, put anything as a stand-in where your head will be, focus on that, and then switch your camera to manual focus. Your focus should stay spot-on after that (especially at f8)
There is too much grey in this image. you need to use lighting (or different tones) to separate you from the background better.
The upward tilt of your chin seems a bit awkward. drop you chin a bit.
Your eyes look a but dull. they seem to be in shadow and lack a strong catchlight.
I am a fan of horizontal orientation for certain portraits, but they usually have some asymmetry. Here, you are posed fairly square to the camera. I don't think you used the negative space well in this image. You would probably be better off with traditional portrait orientation.
I hope this is helpful (and feel free to disregard/disagree).
Desi