On the surface, an arc seems rather simple to understand and easily put into animated applications; but without regards to the forces at work, the path of the arc might appear hollow and mechanical, lacking organic senses.
In common-sense physics, soft forces allow higher degree of curvature, creating lyrical and more complex series of unfolding arcs; stronger forces cause arc to be straighter and simpler, lesser in degrees of flexibility.
These tutorials cover basic character poses in steady balance, dynamic balance, and out of balance. How a character's pose is related to weight shift is described as well as how characters' movement causes them to gain gain or lose weight.
Do not discount their simplicity! Here you have all the principles of animation being worked on, these fundamentals id what all other animation is built on. They are worth your time and effort to explore, experiment, practice and re-discover.