Hey, i would look into the lightmap resolution as i see a lot of artefacts on intersecting surfaces. If you are unfamiliar with lightmaps i suggest you search a bit for best practices around that, like cutting out geometry that is not visible, etc. The materials look interesting but there is almost always a sharp…
Cant find much to critique, except for the materials. Metal and plastic are almost identical on your model, i think they should be more distinct here, even if in real life they are very similar. Another issue is that the edges are very sharp in some places. By making them a bit softer they will read better at some distance.