I have accounts on three instances but I’m unsure which one should be my main account.
Ideological similarity.
Do the admins federate/unfederate from instances you care about? Do they ban/allow communities in a way you agree with?
Look at posts and comments from the instance admin. Does this person seem to know anything about running a server or managing software? Do you like the admin’s tone and attitude? Does it seem like the instance will be around for the long-term, or is it someone’s hobby that they may abandon on a whim?
Look at the instance’s ban list. Do you agree with the choices? Maybe you want your All feed to include exploding-heads and lemmygrad, or maybe you don’t.
Does the instance seem to have a community theme that you want to be associated with? Some emphasize LGBTQ+ communities, or NSFW content, or particular political views.
How annoying. I thought the point of being federated was that i had 1 account for everywhere. Now the douchebag running my instance is going to ban certain communities (defederate) on my behalf? The fuck. Do i need an account on every server if i want to see everything? It’s removed. Give me a ban button and open everything up.
IMO the point of a distributed network isn’t convenience or unbridled free speech, but freedom of choice. Not only are there hundreds of instances to choose from, but anyone can run their own instance however they like, including you. If you host your own then you alone hold the ban button.
The transparency in funding and discussion of donations, the country or state it is hosted in (local laws), does its moderation policy align with your values?
If it’s a small instance fewer communities may be federated already so you may need to be the one to manually search for them for the first time (thus adding them to your instance’s “all” feed). Larger instances will already have many communities discovered and a fuller all feed. Though with lemmyverse.net and some determination you can build up the federated communities list up entirely yourself (and give everyone registered there an expanded “all”).
If you just want the most popular and wide range of profiles, go with Lemmy.world
I went on the “recommended instances” section here: https://github.com/maltfield/awesome-lemmy-instances
