For my home server, I have a flat 2507 line docker-compose file that automatically configures and boots all of my 85 containers. I still have some complexity: .env files in /opt/<container>/, a systemd process that automatically runs

  docker-compose -f /<dir>/docker-compose.yaml -d

on boot, and it's only a little irritating to have use absolute paths for everything instead of relative. But, after having to update all of my services manually for 3 years, I will never be able to go back.