To me the best BTC bookie can be subjective, everyone has their own preference on what is the best for them and it might not be the best for you.

If you're looking for the best odds Bitcoinrush has it all. (reference)

If you don't want to use an account and still want to place a bet there's OneHash.

If you want a bookie that offers promotions you could try Nitrogensports.

You can use the link above as a guide to find which bookie suits your needs. Also most of them doesn't ask for KYC upon registration except for Sportsbet.