Why are we running Docker inside LXC? That’s not a wise decision, and is specifically stated as a big “no-no” by both Docker and Proxmox devs.

VMs don’t use as much resources as you realize. I’ve got multiple VMs full of Docker stacks (along with other VMs running various game servers, and several LXCs for various “not set up for Docker” services) spread across three i7-7700T servers; none of them are even close to being taxed.