Federation means it’s almost meaningless which instance you register with, and as integration between instances and other Fediverse apps gets better it will just become more and more meaningless.

IMO, this couldn't be further from the truth. Different communities have different priorities, principles, and technical requirements, and will take different approaches to controversy. Some communities are low-profile and laid back. Others are magnets for abuse and may require additional moderation, and even technical changes, like disabling image embeds (as one example) to mitigate harassment. Some are filled with avid shitposters, while others insist on the utmost degree of civility. Some have advanced requirements for operational security. Some want broad access to the network, while other would prefer a quiet corner. Some might be focused on video and require an instance that can handle the additional bandwidth and storage requirements.

Who hosts your instance is important. The jurisdiction your instance is housed in is important. If a community requires special accommodations for accessibility or other reasons, that is important. If you need moderators / admins who understand your native language, that is important. If an instance wants to go above the technical level and do things like verify users (kinda like journa.host) that makes an important distinction from your typical instance.

In the beginning, we won't know who's trustworthy, but this is the Internet. There will be controversies, and we will see how various admins respond to these controversies. Over time, they will gain reputations, both good and bad. It is best if somebody who already has a good reputation, like a respected mod from another community is able to operate the new home for that community.

For now, it probably doesn't matter where you end up, but as time passes, it is good to keep an ear to the ground and see how things develop. Eventually you will find a solid niche. This is a problem even the fanciest join-xyz-fediservice website can't really solve, but it is meaningful.

it's like email. You need a server somewhere to hold your inbox. They should make an easy way to migrate your user to another instance, though.

It feels like user accounts need to be abstracted away from instances somehow. Federation means it’s almost meaningless which instance you register with, and as integration between instances and other Fediverse apps gets better it will just become more and more meaningless. It should be possible to just “Join Lemmy” and have the servers behind the scenes handle spreading the load. You should be able to login to Lemmy from Beehaw.org or Lemmy.ml or any other Lemmy instance. The way it works at the moment is kind of like content is global but accounts aren’t and it feels like it should be the other way around?

User accounts can be independent of anyone else's instance. You just have to host your own.

But it's always going to be much more convenient to register your account on someone else's instance, than to set up your own. Even if instance setup was made to be as effortless as possible, and single-user instances were made to be as lightweight as possible, say you download and run a single binary onto your computer that runs a lemmy instance and everything is automatic from there, most people still wouldn't want to do that.

The idea that you should be able to log in to your account from any instance is...less practical than you might think.

The technical reasons why are hard to boil down into an easy explanation. But the very short version is that everything comes with pros and cons. Doing it this way makes it a little less convenient for users, and a little harder to make a good UX for. Doing it another way could make it more convenient, at the cost of making it very easy for a bad actor to do things like post fake content under another user's name, or could add inconvenience somewhere else, like making it so that users have to manage a private key instead of or in addition to their username and password.

I do think there's room for improvement, but I think the overall idea of logging in and interacting with content specifically via the instance you're registered with is ultimately very unlikely to change.

This is something that made me stop using Mastodon, too many instances with bad method of connecting them. I'd much prefer that instances aren't seen to the user (I wouldn't mind somewhere with the text "this community is hosted by X on server Y"). But seeing @username@instance is weird and many Reddit refugees won't have any idea what does it mean. I mean, the concept of federated network is complex already.

I've also encountered a lot of bugs in my short time of use which I'd like to see fixed, but I'm not sure where can I report them, or to see if they are reported already.

Noo. Instances are responsible for moderating their users because if you have bad users all coming from one instance then you’ll get defederated, but instances will also defederate each other when drama happens.