This is a neat overview!! I like to federate my posts from microblogs as well, and did some tests.
Here are a few of my notes:
Viewing communities (from Mastodon) - that kind of depends? All communities I follow show up with their posts intact on mastodon (.social), but not when I use a different instance (e.g. mastodon.de) or software (examples: RenPy, Otome Games)
Viewing profiles (from Mastodon) - That also seems to depend on the instance. For example, here's my profile as seen from mastodon.social. Viewing it from my Mastodon account, I can see all of the original posts and replies.
I already tried them out and made starter packs for Visual Novel developers and artists I like. I got a 500 error a few times while trying to add a user to a starter pack, but apart from that it works pretty well. Wish there were better filtering options for the search though.
What S_H_K said, people have reported being rebuked for posting pictures without ALT-text and not CW-ing uncommon things like eye-contact or food, for example. One person notably received angry messages for posting about cutting their finger on a sheet of paper without CW. The worst accounts were of POC talking about racism they experienced and being told to put it under CW.
customizable feeds you can subscribe to + starterpacks instantly give you full timelines and people to follow (and followers, if you're in many starter packs)
better discoverability, and therefore higher engagement
stacking moderation and excellent security features (e.g. detachable quote boosts, "the nuclear block")
many users who tried Mastodon first had bad experiences with "HOA"-like behavior and over-enthusiastic mods
Tumblr - my first real main social media platform, mainly fandom stuff, used to post fanart there as well, I've been on that hellsite for half of my life now and will probably stay there until Automattic pulls the plug
Mastodon - My main Twitter replacement, really good for fandom since it's easy to talk about spoilers with custom CWs
Bluesky - Second Twitter replacement
Lemmy - As reddit replacement with less lazy engagement bait posts (this is really a problem on reddit especially in game-(dev) subreddits
Discord - for Gaming-buddies, fandom communities, and gamedev communities
Yeah, the biggest problem with this approach is different moderation philosophies. You would have to set up a vetted set of approved non-problematic instances. I've read several accounts of people who tried out fedi and left soon after, and nothing sours the newcomer experience more than unknowingly joining an instance with a toxic community/moderators
That could be the case! I do follow my lemmy-account from mastodon, (and the communities I mentioned as well).