Your anatomy is still fairly off on this character.
I've taken account of your most recent edit and IrresponsibleFreelancer's as well, since they made some changes that adjusted but still did not fully correct the problems.

If you look at the original (your most recent edit) on the far left, you can see the skeletal wiring is out of proportion from one side to the next. The character's right arm is longer while their right leg is shorter. The pose could account for the leg perhaps but not the arms. Both portions of the arm are longer on the right side as you can see by the color associations I have marked.
IrresponsibleFreelancer's lengths are closer together on the arms.
On the first image I drew anchor lines for the head/neck and the shoulders to the floor. You can also see the relationship of the knees with the position of the head this way by looking off of the dark green lines. In order for a pose like this to work the shoulder, hip, and ankle of the right leg need to be lined up very closely or the character would simply fall over backwards.
You can see the angle of the shoulders with the head are very right side heavy as well. The left side shoulder is much longer. The angle and positioning of the head and neck suggest a backwards lean.
All of these things come together to make the character look as if he is falling over.
The best way to fix this aside from redrawing him, is to pull his anatomy into better alignment and then redraw that to make it work.
A very quick reallignment:
