Hmmmm...both seem unnatural, The top one with the green stick, the kick doesn't go out far enough and the leg should land in front of him like in the bottom one, seems shaky, the foot that the green guy's standing on shakes, but foot placement comes with practise, during the kick his arms jerky suddenly then jerky back to their starting places, also the entire thing seems somewhat uneased. Work on flow, easing, foot placement, shakiness and before you animate something, assuming you don't already do it, visualise it from two or more different perspectives in the real world or something similiar, doesn't have to be the real world.
That took alot of effort and I think it makes up for the second one.
