Indeed, we have FEPs that either directly address the UX issues mentioned in your post, or could be parts of final solutions:
The Sin of Overwhelming Complexity: Instance Selection Paralysis
- https://codeberg.org/fediverse/fep/src/branch/main/fep/61cf/fep-61cf.md
- https://codeberg.org/fediverse/fep/src/branch/main/fep/ae97/fep-ae97.md
The Sin of Remote Interaction Purgatory: Federation Gymnastics
- https://codeberg.org/fediverse/fep/src/branch/main/fep/07d7/fep-07d7.md (withdrawn; https://fedilinks.org is a similar proposal)
- https://codeberg.org/fediverse/fep/src/branch/main/fep/3b86/fep-3b86.md
The Sin of DM Disasters Waiting to Happen
Some FEPs talk about limited visibility posts and private groups:
- https://codeberg.org/fediverse/fep/src/branch/main/fep/171b/fep-171b.md
- https://codeberg.org/fediverse/fep/src/branch/main/fep/db0e/fep-db0e.md
The Sin of Ghost Conversations and Phantom Follower Counts
Synced conversations:
- https://codeberg.org/fediverse/fep/src/branch/main/fep/1b12/fep-1b12.md
- https://codeberg.org/fediverse/fep/src/branch/main/fep/171b/fep-171b.md
- https://codeberg.org/fediverse/fep/src/branch/main/fep/76ea/fep-76ea.md
- https://codeberg.org/fediverse/fep/src/branch/main/fep/f228/fep-f228.md
The Sin of Invisible Discovery: The Content Mirage
The Sin of User Discovery Hell
I think ActivityPub relays could be used to solve those problems:
- https://codeberg.org/fediverse/fep/src/branch/main/fep/ae0c/fep-ae0c.md
Thanks for compiling that list! We've opened a few issues with FEPs to investigate: github.com/bonfire-networks/...
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