@sblackrose The main issue here is that the lots aren't loaded in high-detail mode. This is normal in general—the game lets most lots look like a blurry mess to save resources. Increasing the number of high-detail lots helps in theory, but there are two problems with this. One is it does still take some time to render each lot, so you'll see a delay if you're panning the camera. The other is that Sims 3 can only use 800 MB VRAM, so information gets swapped out as necessary, meaning that you probably can't have more than about 4 high-detail lots at once (depending on their size and complexity) even if you increase the setting. It also means that previously-rendered lots get swapped out and have to be rendered again.
If this is a problem for you, I would suggest trying the DXVK wrapper. You can find a discussion of it here:
https://www.reddit.com/r/Sims3/comments/1cyrct7/dxvk_and_vram/
I can't offer anything better than that myself because I haven't personally tried it, but I do hear good things... once people get the settings right. It can take some experimenting. But the important detail to remember is that your computer can absolutely handle whatever options you choose; it's just about keeping Sims 3 in check.
Since you have a new AMD GPU, I would also suggest this graphicsrules.sgr edit to make shadows show up:
https://answers.ea.com/t5/Technical-Issues-PC/The-Sims-3-No-shadows/m-p/12226819#M255715