Question: how many polygons is the spider made of? I'm guessing 2k to 3k tris? If so, it's very excessive, and could be a fraction of the count (just over 1k at most). The eyes and mandibles being fully modelled are also too much, they should be part of the texture itself.
1k texture maps are simply too high; I recommend mirroring the body and abdomen's UVs from the left side to the right side, and keeping the texture itself no larger than 256-by-256 pixels at the most.
Lastly, I recommend giving these two pages a look, they're useful references for how the topology should look for PSX style arachnids:
- https://www.turbosquid.com/FullPreview/223436
- https://models.spriters-resource.com/playstation/kingsfield/asset/352657/
That said, I appreciate the effort put into this model, and the fact that you'd put it up for anyone to download and use. I hope my criticism was constructive and helpful!