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Thank you @stellabelle!

I think anywhere from 3-5 would be nice, 2 might be a little too low for people who post quality stuff more than once per day.

and what if they make another account just to upvote "his" comments?

I agree; if there is too much police mentality, people will just work around it with alternate accounts; it has to be more motivational; which is supposed to be the "crux" of steemit in the first place. Find the balance of motivation that works to incentivize the best content creation, and rational discussions.