Installing Home Assistant on your Proxmox installation takes less than 5 minutes and you don't need to run any scripts! In this video we'll quickly jump through the process and you'll up and running in no time.
Discard is not related to SSDs in this case. It allows trim inside the VM to properly work and give space back to the LVM-Thin pool. Every disk on thin storage should have that enabled. I'd also recommend enabling the Qemu Agent.
Not related but can I get some info on your keyboard? If it's a custom, what board is it and what switches are you using? It sounds great! EDIT: Just saw the custom boards in the background. Nice to see a fellow keyboard enthusiast.