You captured some great expressions here! I love all of these poses. My problem is with the background and the floor. Imagine if you had a wood floor and a white background, which would reverse the general colors, I think it would look much nicer.
The white clothing in most of these shots seems to blend in with the floor, and sometimes both are overexposed. Even in 4th shot you almost avoid it because the jeans create nice contrast, but the feet are blending into the floor with those white socks.
The background by itself, isn't so bad, which is why the 3rd shot is my favorite. The hat throws in some more color too.
If you can't change the background or floor, then try just dressing the baby in more colorful clothes.