Attempt at making a 2 tiled base.

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Naturally when we walk, when we put one foot forward, it's the opposite arm that swings forward. I.e. when you step forward with your left foot, your left arm swings back, not forward with it. Its a pretty common mistake when making walk animations. I'd also suggest making the legs in the step frames straighter and more dramatic of a change so it doesn't look so much like he's shuffling around.

If you wanna step it up a bit you could also separate the standing frame in the animation and replace it with one with straighter legs so it flows better.
In response to AmonR
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CC please