The Ariel figures wouldn't take a lot to fix, but it's sad that they messed up on such simple details. A huge amount of the issue is incorrect/nonexistent makeup on the face. No eyelashes or lipstick. Eyebrows are the wrong color (they're supposed to be black, not red). The irises/pupils are way too large. And while she doesn't have any cheek blush in the film, the AA being a physical 3-dimensional would probably benefit from it to give the face more depth and fit better with the dark contrasty lighting. They should also at least have added actual texture to the hair for the same reason. They added an actual wig on the above water figures in an early renovation and it looks tremendously better than the rubbery/plastic texture still present on the underwater variants. There are probably some other tweaks that could stand to be made as well. Overall though, a very poor and off model figure.
Some of the problems are also the result of the lighting and skin texture. The skin looks far too shiny and orange, and the lighting is way too bright (especially in this scene which is otherwise lit with a subdued dark bluish hue). So either give it more of a matte finish, or (and this is the better solution IMO) use old school black lighting. Lighting the entire ride with dark light would also help hide some of the backstage elements (if they're painted pure black) and keep the lighting as a whole much more uniform and controlled. They did add SOME black light in the Under the Sea scene in the early renovation (also revising Ariel's hair in the scene), but it's very awkward as it still switches back and forth between regular and dark light.
