There are two big things that I think would make this MOC stand out a lot more:
1 - The Colorscheme and Color Blocking
While your range of colors isn't too varied, there is quite a lot of colors on this MOC and it makes it look a little messy and hard to follow. For dark colors you have brown, gunmetal, grey, and black; for the brighter colors you have lime green, dark green, and translucent green. Try cutting back on some of these colors so that they are more cohesive; for example, maybe swap the grey bones out for black ones, and get rid of dark green or translucent green.
This is where color blocking also comes into play; you want to try and clearly separate which parts of the body are which; constantly switching back and forth between colors can mess with this idea and make all the limbs blend together.
A great example of this is Mitch Henry's self-MOC Zeren; this is the original version:
This is the most recent iteration, on the other hand:
You can see how much cleaner the new version is; the old one has black showing through nearly every section, and it ends up cluttering the MOC. The new version, on the other hand, has excellent color-blocking and it makes the figure look phenomenal.
2 - Photography
The second biggest thing with MOCing in general is taking good pictures. The white background is an excellent start (some people can't seem to understand that a messy bedroom doesn't make a good background) but the picture is still rather dark. Try getting some desk lamps (2 should be good to start) to get plenty of light; if you want to go a step further put paper over them to disperse the light and limit the glare on the figure.
Hope this helps!