The problem I have always had when building elaborate home server setups is the "set it and forget it" nature of the systems I've installed bites me in the ass. Since it's not my full-time job to manage these systems, I'm really not familiar with them the way I might be with the systems I manage at work. These systems cruise along for years, and when something finally does go belly-up, I can't remember how I set it up in the first place. Now I have a giant chore looming over me, ruining a perfectly good weekend.
These days, I design everything for home with extreme simplicity coupled with detailed documentation on how I set things up.
Docker has helped tremendously, since you can essentially use an out-of-the-box Linux distro with docker installed, and you don't really have to install anything else on the hardware. Then if at all possible, I use standard docker images provided by the software developer with no modifications (maybe some small tweaks in a docker-compose file to map to local resources).
Anyway, my advice is to keep the number of customizations to a bare minimum, minimize the number of moving parts in your home solutions, document everything you do (starting with installing the OS all the way through configuring your applications), capture as much of the configuration as you can in declarative formats (like docker compose files), back up all your data, and just as importantly, back up every single configuration file.