What conditions must be met before proxy voting is enabled?

This poll operates like a wiki: feel free to update its summary and, if applicable, add a new, better option to the poll itself.

Proxy voting is currently disabled on this web site. It was a great feature that we used for a short while, a long time ago. However, there were important shortcomings to the system which made it somewhat unfair and biased in favour of old proxies with many clients.

We'd like to reenable this important feature, but before we do so, what conditions must be met and what software improvement must be effected before we turn proxy voting back on again?

Note, this is not a poll on what proxy features it would be cool to have. For this, see the following poll instead: What improvement would you like for this site?.
Instead, this poll is about the minimum features and conditions to meet before we can start using the proxy feature again.

See the developer's blog entry: Proxy voting disabled for the time being....

This poll is listed in the following wiki page:

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