What would you say is missing from the mastodon user experience vs twitter?

Things I would like:

• better discovery/suggestions when people first join. I get a "selling point" is that the timeline isn't algorithmically driven, but just to help people get their feet wet start showing them some stuff
• when displaying a post there needs to be a better mechanism to fetch all the replies. Right now it's possible to respond and say something someone else already did because you you're not shown their reply. For federation reasons I guess.
• better list integration

But overall, for me the functionality I used from twitter I have on mastodon too. The real missing feature is the huge variety of people, and getting that takes time.