Had fun with your design
I agree with a few of the suggestions in here already including leg length. I am very new to pixel art but I am loving it, so many techniques. I am focusing on hue shifting, which I think is really important from what I have learned so far. trying to emulate natural light and shadow is really cool, as well as using complementary colours in shadows. I did a few things here. made a few ramps going from green to green-blue and then blue to light blue. used that for most of the main colour work.
altered your jacket to be a blueish red, mainly just to see how it looked, adding more blue to the shadows. had to rework the palette a few times while working.
The important thing i learned with this exercise is to pay close attention to the saturation/value of all your midtones and work from there. The Saturation and Value need to be in line with eachother across all colours; i.e: they need to be roughly exposed to the same amount of light, shadows/highlights excluded. The most important thing is value/saturation, allowing you to 'go wild' with hue. Im no expert though clearly. I had to eyeballed the colour relationships as i worked. GL with your work.
Sonicspin your edit looks amazin love the use of green shadow. so appealing.