I have been experimenting with ball and socket joints since I first got the MakerBot years ago. Took a while to find a combination that I am happy with. This iteration is a 0.4" diameter socket with a .403" diameter ball. This provides some interference on the joint so that it holds position. Unfortunately, with the creep in the PLA the joints over time to soften up. This joint provides a bit over 180 degrees of rotation in the primary axis, without controlling the rotation along the limbs axis.

This is a posable figure that is intended to be a framework for other parts. I am working on different sets of heads and covers for the torso and limbs that would snap over the frame.