1. The nifty fifty isn't the best for this type of photography. If you want to shoot architecture or landscapes go with the widest angle you can get, crank the ISO down as far as it will go, the aperature as small (big number) as you can, screw on a CPL filter, use a good tripod and a remote for the shutter release since it'll probably be about 1". You'll notice a huge difference.
2. Has good use of DOF, the face seems very sharp on my monitor, The tattoo is what I would call "half out of focus" and the hand is even further. Most importantly this image seems to tell a story and it has emotion in it. The image tells me: Long road trip to see good friends with Bon Jovi cranked as loud as it can get. The only negative thing I have to say is the mole/freckle on the neck is a little distacting, but nothing some PP can't fix. The only possible improvement I see would have been to shoot the same shot while passing some buildings or something with ISO at 100 to give you more motion blur in the background.
3. Use a good tripod and remote shutter release. That will allow you to use a longer shutter speed and keep detail by lowering the ISO. IMO anything above 800 ISO should only be used by journalist, not artists. Print this picture as large as you can and tape it to inside of your front door. Then in permanent marker write across it "WHAT NOT TO DO". I mean no offence by that, just that you'll learn more from your bad pictures than your accidentally good ones.
4. Maybe it's the bourbon talking, but I like this one. It has emotion, and it causes me to look at the picture longer to try and see the story and a few different ones come to mind. Just once again I wouldn't use such a high ISO, but in this case I can see it possibly being a self portrait or something which would make using a tripod and remote very difficult.