I don't envy @CobaltVelvet's attempt to moderate their instance. Like, I recognise how important it is, and getting user buy-in is actually one of the best way to do it.
But wrangling Internet randos — and I count myself as one of them — into buying in to your policy and then dealing with the administrative work of ensuring that the policies are followed... is grueling, thankless work.
Hence that decision of wanting an instance for friends only. I'm guessing calling out friends will be easier.
@tariqk @CobaltVelvet Random thought just occurred to me.
If there's a way to flag a toot as inappropriate, and that is fed to some list that admin has access to, then the hand-moderation of those toots can be fed in to a neural network which runs in parallel but doesn't affect moderation results until it's capable of matching the hand-selected moderation outcome to a certain degree of accuracy.
FWIW, I don't know much about NNs, but this seems to be the kind of fuzzy task they're great at...
