Looks good, I use a lot of the stuff you plan to host.

Don’t forget about enabling infrastructure. Nearly everything needs a database, so get that figured out early on. An LDAP server is also helpful, even though you can just use the file backend of Authelia. Decide if you want to enable access from outside and choose a suitable reverse proxy with a solution for certificates, if you did not already do that.

Hosting Grafana on the same host as all other services will give you no benefit if the host goes offline. If you plan to monitor that too.

I’d get the LDAP server, the database and the reverse proxy running first. Afterwards configure Authelia and and try to implement authentication for the first project. Gitea/Forgejo is a good first one, you can setup OIDC or Remote-User authentication with it. If you’ve got this down, the other projects are a breeze to set up.

Best of luck with your migration.