So the first option is to set up Mastodon, Pxelfed, Kbin, and whatever else on your own domain. It's even possible to get most of them to use SSO, which is really well done. I took a look at https://v.st/ and I was impressed by all the services they've stitched together and made easy to setup.

It requires you to maintain all those apps and have some sort of docker service to run them, but that's doable

I suppose my main objection to this sort of thing is that these apps are all designed for large numbers of users, and the amount of infrastructure needed to run them is pretty big, that then requires a lot of upkeep for a single person service. If I wanted to add something like a writefreely instance to it, then I either have to work out (and possibly code) an SSO plugin, or accept that it will have to have its own auth.

This might be an easy way to get started at #SelfHostingFedi, whilst one waits for something better to come along, but it's far from optimal