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We're stuck between making it as easy as possible for new players to get started on the site (easy to make an account, free dust from the faucet) and making it hard for spammers/bots to abuse the system. I don't see a way of satisfying both of these requirements without human intervention (ie. intelligent mods).
WE ?

WE? who are the we that you're referring to with? i can only see is you lol
We, as in people who would like to provide a faucet on a site but can't find a way of doing so without it being botted or abused in other ways.
I used to run a couple of dice sites. I would have liked to have been able to automatically give new users a few bits to play with, but couldn't see how to do it reasonably.