Consider adding following to the the “Hides” category:
Eyewear,
Hat,
Earring,
Top_head
OR
descrease number of polygons used in this model. For example, it wouldn’t drastically affect the initial shape of the model, if you simplify the area, marked on the attached screenshot.
As of now, the GLB contains 4 copies of the same texture, and all 4 are used in 2 materials, that differ only in applied emissive values. I suggest making a proper emissive map, where you control emissive value via brightness of pixels, thus you can end up with only two texture maps and 2 materials (the AvatarSkin material and the SharkHead material).