I think you're overusing adjustement layers wich end up having a bad result in your sig colours, in some of them they're kinda dead in other ones they look oversat, etc.. So yeah you should work on colours.
Your lighting is pretty cool, you could improve it getting a better hold of burn/dodge tools. I don't like the "Hi" tag, colours are messed up, depth aswell, some places are oversharpened and you didn't do well on lighting in this one.
I like the quality of your tags, quality is something every artist should take care of when getting resources and I can tell you got a good hold of it when I see your work.
Overall nice sigs, I'd like to see some smudging tho to see how you do, idk something different.
KIU