This is some impressive stuff, but there are some kinks to work out with your technique. The excessive frames used when the character is only sitting down make it messy, not alive. Having him adjust his posture or look up slightly with just a couple of frames would look way more natural. And his head blowing in the wind, when he's in a completely silent void doesn't look great either. Sometimes the arms are desynced with the legs but that'll pass with some more practive