Hi,
this post is from last week, if you still would like some C&C, if I can add anything it'd be to work with super simple shapes to nail down the movement first, here's an example

when it's just rough shapes you can adjust the animation to exactly what you want quickly and easily, for example, if part of the animation pops frame to frame for the shoe position, you can just move the shoe slightly, but since you moved the shoe, you'd have to re-draw the whole leg, so redrawing the shoe and leg is easy if it's just rough shapes, like a leg could be a cylinder with a ball on the end for the shoe
and for your latest run cycle, I think that the part where the character's left leg first touches the ground after travelling through the air in the stride is missing a frame compared to the timing when the same motion happens but to the right leg, it that makes any sense