Polycount doesn’t matter too much, try to keep it in the 40,000 tri range at the high end. Lots of small tris have more of a performance impact than more evenly space tris, so it’s more about how you are using them, than how many there are. But that only really matters when you are looking at an interactive scene. You can really go crazy if you are just doing static images or a captured video.
2k-4k textures are the norm. If you need more detail, use tiling detail textures instead of trying to use a 16k texture for example.