Woah Jessica! I agree that it's a level up! So you asked for a critique so I'm going to deliver. Part 1 is how to make the image look nicer and then the other part will be about how to make it look more realistic (which I acknowledge isn't necessarily the goal). It looks like her right arm and hand (left to us) needs more reference as both sides of that forearm look too symmetrical and where the hand meets the forearm isn't believable. The hand is also getting some pink outlines that do not match the lighting. I like that you didn't use a bubble brush to create the bubbles but they do look like they are venturing into symbol territory so I would vary that white outline more and make it perhaps disappear in some spots. Along similar lines, Ursala's tentacles can be a bit too outlined at the bottom. You can lose edges more often or let things be silhouetted rather than feeling compelled to put that edge light around things. For instance the lowest eel is outlined a lot and I am not sure it is necessary. Her tentacles are feeling divided between two planes so I would try to make the distant ones perhaps a little darker towards her body to make them feel more a part of her and make the left tentacles shadows a bit lighter so it feels like it is going back in space. I would actually look at lightening the background behind her distant tentacles a little bit.



Now for the bit on realism which you can really take or leave. For instance I just recently did a mermaid pic and I probably did not follow the advice I am about to give because I was shooting more for poppyness than realism. So generally scenes underwater won't have sharp highlights or bright highlights or sharp shadow lines because the rays of light are getting too diffused and deflected by the water it is passing through. So we probably wouldn't see that sharp shadow of the breast against that arm on the left or the sharp highlight on the arm on the right. This also means you don't get much as far as rim light. This is based off a Disney cartoon though so I'm not saying you should necessarily follow the laws of nature. If you want to willfully break the rules you could vary her skin some more. For instance if this weren't underwater that light she is holding would be penetrating her skin and scattering right before the shadows raising the saturation of the color there. The water would give her skin a somewhat homogeneous color but if you want to break the rules you can make the skin above bones slightly yellow and cheeks and nose slightly more red.