Would it be possible to track more statistics? (some potentially gross ideas)

If we really want to figure which instances to suggest, it could maybe be good to have some additional statistics tracked per instance, and compare to the global averages. It might even be able to influence default choices for like the join-lemmy website.

I understand this might sound gross, but maybe there's a good idea in here?

• user retention (percentage of users that are still active after 6 months? 1 month?)
• percentage of anonymous visits that result in a signup (ignore those that result in a login)
• ban rate
• signup acceptance/rejection speed
• percentage of accepted signups vs failed/declined (maybe this just promotes accepting spammers)
• average time spent on signup page
• bounce rate of signup page (opened but never completed)