Had to upload to one instead of my main because of network errors
Sooo, I'm still wrapping my head around the Fediverse as well, but my understanding is that you kinda have to plan for instances going down on a regular basis. I don't mean server outages, I mean somebody saying screw it, I don't have the time or money for this, anymore, I'm out, and shutting it down, effectively forever.
The theory of it seems to be that we expect this as the price of the Fediverse and build it into the design of the whole thing. Thus, you should be able to lose an instance while still keeping most of what you're here for, thanks to being able to do weird-seeming things like follow Lemmy threads that show up in your Mastodon feed, if you know how to set that up.
Mastodon is specifically designed so that you can migrate all your follows and everything else to a new instance, literally pack your little bags and move along. Because somebody might decide they're done paying server fees on your instance, or maybe the community just sucks, and you'd rather move. I've not had to do that, yet, that's just my understanding.
It's how you design around the servers (instances) basically being user-hosted for kicks. I don't think Lemmy is quite so elegant about it, though. It's like 50 guys standing up saying, "I am Spartacus!" except they're all Lemmy. Sorta gets the same job done. If one soldier in 50 goes down, 49 still stand, and that works, too.
So yeah, go ahead and follow five instances. It's kind of your only option when a favorite instance decides to de-Federate, but you still want to be on the rest of Lemmy, too. I think we got a Pokemon model, here. Gotta catch em all.