Somewhat agreed with SilverBrick. While we don't necessarily need to see more related artwork, it would be good to know what you're aiming for - is this for a game, an adoptable thing, for fun...? Will it be animated, or is it a one-off still sprite? Will there be backgrounds that go with it? Is this meant to be side-view, 3/4 view, or something else?
I think the silhouettes are rather boring, though the feet on the left one do help with that. The legs blend together, consider placing them apart. The short 1px-thin arms are likely to get lost against any non-solid background. Thickening them up could work, but they'd be look fine as-is against a solid non-midtone background (dark or light).
The trousers are very blue. If it's meant to be denim, consider lowering the saturation. PVC clothing and such can be that bright, but denim usually aren't.
The suspenders(?) are difficult to see because they blend into the shadows. You could lighten the shadow on the shirt to make them more visible, or make the suspenders lighter than the shirt rather than darker. The light bit of hair similarly blends into the skin shadow colour, and the quick fix there is the opposite - darken all the skin shadow colours so that the hair stands out more, or darken the light bit of hair.
The arms feel a bit short to me, but making them 1px longer might feel too long. Perhaps it's worth a shot?