Not bad so far. I think what I like best is how the human skin tone meshes well with the seaweed green of the fish tail; I get the impression brown, yellow-green, and gold could be the dominant colors. That particular palette of colors I wouldn't name as the most luminous, but I believe they could complement each other naturally. The sea pony and it's bright blue makes for a cute contrast as well.

My suggestion: keep the base colors but add bits and pieces to add a little shimmer (most obviously when you sketch the scales); the bright green of her top would be one example and her jewelry another; basically break the monotony of the brown-yellow-green-gold now and then while keeping it dominant. Because of her coloration, seaweed in the background would make sense unless you want her to contrast more with open ocean.

What you have so far looks good, stick with the earth tone colors if you can when you keep on working on the mermaid. An just like Redliox about the colors, try using a bit of god or hints of it. That would be interesting to see

Coming along nicely, I think. And that sea-pony is just adorable :)

thank you :)