Putting personal thoughts aside, Imma be blunt and say this seems kinda hyper-specific for a community.

Honestly depends, but if you want an all-around good instance on a misskey fork, try lethallava.land

Honestly Misskey forks for all their flaws can absolutely take this opportunity to properly advertise themselves as viable alternatives. As someone who uses a Misskey fork, I love the UI in comparison to Mastodon, and the communities in Misskey forks are a lot less techie and a lot more laid back and goofy most of the time from my personal experience.

Okay, but which one is easier for diagrams?

I’d say use the left for diagrams, and the right for reference as to how things look on the inside.