I've been thinking about implementing a two-tiered Faucet: one that gives out a smaller number of coins and just requires you solve the CAPTCHA (and has all the current anti-cheating measures in place; [...]
And another that gives out a larger number of coins if you login with a valid Google account. [...]
Ack, please not Google! They make the 'net too centralised already.
But if I did do that... I'd get accused of implementing the Faucet as a sneaky way of stealing Google account email addresses.
Piff. TANSTAAFL.
You could delay the gift for a while, to see who else shows up asking later in the day. Then if it looks like someone cheated, you can cancel all their pending transactions. This way, when they game your rules for spotting cheats they risk all their effort in (window of time), rather than the effort for one more drip.
Or you could require the recipient address on a postcard with a nice picture, if you don't mind publishing a snailmail address.
It might help if you made it clear what you regard as fair..? I asked once & got 0.05 (thank you).
Not being sure that you are happy for me to ask again, I didn't.