This has come up before and my opinion is still the same. I don’t want karma because it lowers the level of discourse. People posting the same running jokes, etc for the karma.
I also don’t know how this would work on a federated platform. Comments and votes are sometimes in a state of flux as data is synced among instances. Raises the question as to what the “real” totals are.
Should work for an instance of the set size you are looking for (250).
Since you will be looking through post history to see if the user is active, are their certain behaviors you see that would disqualify a user from joining?
What is the benefit of this over just running Wireguard?