My view (omg a personal experience!) on avatars had always been that they are a type of 'badge of honor' rewarded to the few for exceptional success (note this can be interpreted in many ways).
Thus, the idea of "personal avatars" doesn't really sit well with me. I wouldn't, however, be against a 'Profile image' idea.
So you could have a profile image you can upload and have visible when someone opens your profile sheet in the client, and it would function like any other profile picture in any service ever. Ofc, this would require client and backend work, which we obviously are lacking people for as it already is, so I'd sooner place it on the back burner of "things we'd like to have but aren't high priority".
That being said, I'd still keep avatars as a way of marking those with special contributions and achievements. And not as a way of personalizing one's profile on an "everyone" basis.