Monetizing is what ruins other places.

I like the way my home instance does financial backing through an open model, and that’s part of why I chose it.

An ideal is enough contributors to keep the lights on and to reimburse the admins for their time spent in keeping it afloat. Moderation should always be a volunteer position for those that want to support their individual communities.

Any excesses in finance I would hope go towards future running costs (to a point), feature development and then charitable donations in that order. Non-profit on paper and in practice.

This is viable for a small instance. Maybe even larger ones if the users are altruistic enough as a whole.