Hello,
Yes, the current version of OpenPanel is entirely free. In the future, we plan to release another premium version with additional features tailored for hosting providers, such as WHMCS module, REST API, and private support. However, rest assured that the free version will always remain free.
Unfortunately, PostgreSQL and pgAdmin are not currently available in the panel. However, integrating them should be relatively simple. I'll create a feature request on GitHub and explore the possibility of adding them in future versions.