I'm definitely interested in seeing how the single-user instance offerings develop across the various federated applications. I have no interest in taking on the role of admin or moderator for people I don't know personally, but am more than happy to run my own front-end service that'll let me lurk and interact with all varieties of ActivityPub content.
For now it seems kbin might win that fight for me since it's equipped to handle reddit-style communities and threads while also providing a workable microblog interface. But it does seem to be a bit on the heavy side... I wonder if we might see some software created for this particular usage scenario one day, if it isn't already being worked on somewhere.