New Custom Fields should feature non-completion of sale if a particular value is selected
To put it simply, if a customer is given a field with a Yes/No radio option and they choose No (or whatever value you want) the transaction will not go through. The new customer fields feature opens up a lot of new possibilities to protect merchants IF the feature could be added that stops the ability to complete the sale if a customer selects a particular value.
Another example: I verify I am over the age of 18 years. Yes/No...if they chose no, then the sale won't complete.