Gregory's Server
Regarding the risk of echo chambers: I believe that can be a risk in the fediverse too - but not due to algorithmic influence and booster of posts.
In the fediverse it depends a lot on who you follow and which topics you're paying attention too. If you only follow people and topics close to your own viewpoints, that can easily end up as a echo chamber as well.
So I advice you to also follow people who you normally disagree with. You may filter out the extreme/radical voices, but at least follow some viewpoints which challenges your own ones. Viewpoints which makes you wonder and question, and engage in discussions if it's not too heated. And be open to admit you might not sit on the only truth. Try to understand why others have a different viewpoint than you have.
That way you get check points towards your own stand points. Which helps you avoid the echo chamber.
But it's a hard challenge. Because we all usually choose the convenient and easy paths. And that's the main "selling point" of the echo chambers. You don't need to reflect on yourself and why you have a certain standpoint.