This is extremely valuable, thanks for this!
As a general question, why did you decide to use a single postgres container for multiple services instead of multiple, stack specific containers? When I first started working with containers I considered your scheme for the sake of minimalism, but didn't want a single container to bring down multiple unrelated services. I also had the resources to accomodate the redundancy.
At the beginning of the pandemic I looked into ways to de-Google and found Nextcloud. It wasn't the easiest thing to start with, especially for a novice, but I had the time and the hardware, and I'm the type to not mind jumping into something difficult if it means solving a specific problem. I then found out about Bitwarden and had a great experience setting that up. After that I was confident enough to try hosting anything I could find. It's been good times ever since ๐