Also found in a !fedibridge@lemmy.dbzer0.com post by @biltong@piefed.co.za : https://piefed.co.za/c/fedibridge/p/22233/post-on-r-buyfromeu-on-the-recent-surge-of-users-to-piefed
I like the way Voyager does it:

DeltaChat also has a very easy onboarding process: you just put your name, and that’s it. The app creates the password in the background and allows you to switch servers easily. That really helps with onboarding new joiners.
Piefed.zip could be a nice default choice. If there are others you see, feel free to suggest.


Yes
Yes. Federation allows any server to maintain lists of trusted and blocked servers. On lemmy and piefed, you can visit
<address.com>/instancesto check it - the link should be at the bottom of the homepage. If I’m not mistaken, most servers also take a “trust unless we manually block” approach, so new instances will show up by default.This is a double edged sword, but it thankfully errs on the side of safety. Blocking servers means you can ensure that no communication from any server that has shown sympathy to extreme content or spam will reach the one you’re in.
Big public instances are often federated with one another, which is what the majority of the users want, so you won’t be missing out.