stupid question I know but let me explain. I self host only because I love learning random things and this was just another thing that I convinced myself I needed to learn, not out of necessity. I am hosting an *arr media system right now but that is pretty much the only thing I actually need, I have unlimited google photos so I don’t need Immich, I am happy with bitwarden so I don’t need vaultwarden, don’t need home assistant, nextcloud, bookstack etc so what I should I self host? throw any idea you have at me.
I’d focus more on the infrastructure instead of choosing what apps to run if you want to improve your knowledge. Running an application is easy. Automation, security, observability, etc. is the hard part.
Learn about Ansible, Terraform, GitOps, backup solutions, logging, network security, etc.