Jim’s Garage on YT, he recently did a video about running Docker in an LXC. I think you’ll find the info you need there. It can be done, but if you’re new to Docker and/or LXCs, it adds an additional layer of complexity you will have to deal with for every container/stack you deploy.
You can use lists in Readarr. Set up a Goodreads account, link Readarr to a list in Goodreads. Any books in the list will automatically be added to Readarr.