I made a few tweaks with the outlines and contrast, didn't wanna change it too much though.
Agree. Add contrast, shift hue in darker and lighter tones, get rid of outlines.
youre other pictures are fantastic, but this..? nice sprite but not a really nice shading and not so good colors. clean it up, than i will be good, i think :)
Nice. Could've used some stronger highlights. The xenomorph is smooth all over.