The trickiest part will be having users pick an instance, but once past that hurdle, the federation aspect doesn’t need to be a complicating factor.
Yep, that’s the thing. When Mastodon was hot for a while, most complaints I saw were about people not getting that they can pick almost whichever instance and/or having trouble deciding because they didn’t fully understand that it usually matters very little.
For a time in the early 2000s I used IE via AvantBrowser. It had some cool features at the time! 😅