I love the highlights! :o

also if you want color theory / palette advice i suggest checking out the Pixel Grimoire (https://medium.com/pixel-grimoire/intro/home) bc it's a great guide and i found it helped me a lot with my skin-making, since it's essentially pixel art applied to a model

i'd say those single pixel highlights tend to look odd, not to mention they look a lot brighter compared to their other shades, contributing to the effect of them looking out of place.

i'd say you should consider larger highlights, and depending on the color, have two dif types of highlights: subtle ones, and bolder, fewer ones