Alright, here's an edit
I did a lot of high level tech (that sounds like rpg talk!) on it so it's a bit difficult to explain it all to someone who isn't as used to the sort of Pixelation skillset. But if I can't explain it, then my edit is useless so I'll try. Prepare yourself for text.
Stance is the easiest to explain. He was a bit flatfooted, I have him a dynamic stance. Not much to it. There pertain a few anatomy crits to fixing the stance though, so here they are: knees where too high I felt, so I adjusted accordingly, left arm was too long and oddly shaped, right arm didn't seem to me to be a straight shooter's pose, so I made it a bit... straighter.
Colors: oh boy, it might not show it but colors is the biggest thing here. So ok you like primary colors, and you like high saturation, that's fine, it suits a lot of subject matter. However your color selection can be tightened up, many colors can be reused. The concept is this: you have three big ramps here (pants blue, shirt blue and the browns). I merged the browns with the skin shades for natural reasons. Now the three different ramps need distinctive colors in the middle of the value range, but at the extremes where they get really dark and really light, they can easily (all three ramps) converge on single ramps. This is a key trick in pixel art, it makes the art more cohesive and as a byproduct it shaves off a lot of colors in the index. You might ask yourself "and why do I need to have few colors in my piece, Helm?" The answer is simple: more control. You can reuse colors smartly like this and the end result as far as I've seen thus far (in my considerable years of experience) is *always* better looking that straight-ramps like capcom stuff. It takes more time, but it's worth it.
I turned down the saturation some on a few indexes, I use a lot of high-sat next-to-black darks to punch color identity through usually, but as you have main values that are high-sat, you are not really at a risk of losing color identity due to washed-outness (as much of my art does) so I left the middle shades strong and eased towards grayer darkness (which is more realistic if that's your bag, incidentally).
Check out how I used for example, the jeans strong blue on parts of the shirt to give some folds a bit of life, or how I used that muted greenish blue on the far lower leg to give it less priority than the front leg (his right one). These things are nitpicks, but if you pile along the nitpicks, you get a piece that goes from 'okay' to 'great'. They will not fix a fundamentally flawed piece, but that's why I started with anatomy and posture critique.
Outlines: another big thing. There's various schools of thought on outlines. If you insist on outlines-all-around, be a sane person and DON'T BREAK THEM. You'll get fat looking sprites like this, bu some people like that. If you break them, you just arrive to selout. What I am doing here is not an amateur technique: I am doing outlines, but they're mostly dictated by where the light source is. So under the arm, darker, on top of the arm, light suggests the outline. What a lot of people miss in this technique is that I do not confuse the line
when I go from one shade to another. I don't change colors in the middle of a 'step', I wait until the angle of the outline changes and then make it darker or lighter according to how much light will hit there. This is imperative for doing this sort of outlines correctly and it took me a lot of time to figure out why. It has to do a lot with avoiding single-pixel noise on outlines (awful, selouty) and also avoiding banding. BANDING is a very big issue, as the years go by it seems to me it's pretty much one of the biggest issues ever in pixel art, and it's not yet well explored by anyone. I will attempt to cover it extensively at some point. You don't need to worry about it much at this stage, and especially in such a small sprite where some banding is pretty much unavoidable. If you want to learn more about this however, you can search the forum database for "Banding". There's a lot of threads where I show how to take care of it discretely at least on a basic level.
I hope all this helps.