Hm...
- an editing window (even two minutes would be better than nothing)
- an archiving feature (allowing me to select a toot or a chain of toots and send the contents to an e-mail address or to some other destination)
- some way for people to voluntarily untag themselves from conversations
@kara_dreamer Regarding the third one, you can already mute a conversation since Mastodon 1.4.