1. A little too close IMO. Additionally the image is at least 1 2/3 stops under-exposed, and with no catch lights.
2. Two main issues here are missed focus and a messy, distracting background.
3. per #2
4. Image is not level, and is grossly over-exposed on the child's skin. Bouncing your flash off of the ceiling here would have been the way to go.
5. Interesting...
The number one thing that I believe you need to do to improve your images is take more time. Right now you have snapshots - to take them to 'photographs' first find a nice, even background which is preferably monotone and non-distracting in nature. Pay attention to your point of focus; with people, always, always, always make sure the eyes are in sharp focus. Try and use sufficient DoF to have the whole person focused, but the background soft and non-distracting. Also, practice your exposure and metering as well as flash work.
Just my $00.02 worth - your mileage may vary.
~John