Having your own domain is a great start to be independent online: if you have a backup of all your content and don't use totally strange features of the underlying platform, you can easily move your content to whatever hosting you want while keeping your URLs intact.
If you want to look into what other people are doing with "my domain is (the center of) my social network", check out the community at https://indieweb.org – some clever ideas & tools around communicating updates etc between sites and integrating with existing social media where necessary.
If you want to look into what other people are doing with "my domain is (the center of) my social network", check out the community at https://indieweb.org – some clever ideas & tools around communicating updates etc between sites and integrating with existing social media where necessary.