Things I would personally like:
-deeper integration with github, seeing metadata from your github profile on your social network profile
-easily embed code and context in the tweet equivalent. Would be awesome to have formatted, maybe even runnable, code snippets
-twitter spaces for developers that includes code or screen sharing and ways to bring people "on stage" to not just talk but multiplayer control or share another window to the space to show what they're working on or explain a concept together and answer questions (twitch streaming with more dev focused integrations)
What would you add?