[2020] Issues from perspective of long-time player

1. This is just the beginning of the new system. More details are available here.
https://community.7daystodie.com/topic/21228-looting-progression-plan/

2. Agreed, and also something that is getting some work in the future.

3. I have never had this much of an issue with it.

4. The system is still being worked on and tweaked, but is currently close to completed.

Performance and optimizations.... This is something you do after you leave Alpha development. We aren't quite there yet.

Your friend with the 3070 may have some other issues. This is a Voxel game. It depends more on CPU and RAM than the GPU. If you guys post your details, I'm happy to help you figure out where the bottleneck is, and how to fix it.
Here is an example.

Also, just for a reference...
Minimum hardware test a18/19

Part of your issue is going to be the resolution. This game isn't designed for 1440p or 4k. Due to the nature of the Voxel engine, the higher you raise the resolution, the more it will stress the CPU. I would recommend setting it at 1080p, and then capping the FPS for this title to 60 in the Nvidia Control Panel.

While the CPU isn't bad, my overclocked i7-3930k benchmarks right next to it with a mild overclock. With extreme OCing, I can get about 10% faster. Pushing my old system on a mild OC (4.25Ghz is mild. I can get to 4.5 pretty easy, and extreme is 5.1GHz.) with 32GB DDR3 in quad-channel, and a 1060 6GB GPU I can get stable around 110 with the occasional dips into the 80's.

You'll want to make sure that the client is fully excluded from security software, and to kill any bloatware you have sitting around. Most pre-built PC's are well loaded with useless bloat.