Refining has stages
You start with a concept and work your way to something good.
Doesn't matter where it starts you eventually want a visually pleasing piece.
Half of your guys right bicept reads as a shoulder, the square white pixels, if this is supposed to be the shoulder it's too low and that'd make his arms too small.
I think his left shoulder is too far out.
Your character doesn't have a groin area at all.
And I don't get why you wouldn't like the upper body yours is messy and block jaggy pixels, I'm to assume that you would eventually apply proper AA where needed.
Look how messy your arm is, I see tons of bridging of colors where a color lines up with another shade, it just looks sloppy to me.
I can't clearly see any volumes in the arm at 1x zoom.
Just kind of looks like a blur of colors.
Looking at some of these frames and they don't even look feasible to be in such a position.
He looks like such a gimp seriously, his arm streches and bends in such ways because you're afraid to draw each frame singly without the other there as backup.
I wont lie I do the same thing a lot when I'm lazy, but it leads to a bad animation I think.
His back arm doesn't seem to move at all.