When people say its M&L style, it usually means it will fit in with the official sprites. Try making it look more like a real barrel, in terms of shape, but still keep it cartoonish;
Try it again, and post in Sprite Discussion for from criticism, sooner or later you'll probably get it right, and then you can try submitting it again.
Try it again, and post in Sprite Discussion for from criticism, sooner or later you'll probably get it right, and then you can try submitting it again.