WP User Avatars allows registered users to upload and select their own avatars.

• Download and install using the built in WordPress plugin installer.
• Activate in the "Plugins" area of your admin by clicking the "Activate" link.
• No further setup or configuration is necessary.

Right now, not very well. We're working on this soon.

The WordPress support forums: https://wordpress.org/support/plugin/wp-user-avatars/

Yes, please!