The block list doesn't support wildcards, but that is something we can add to the wishlist along with your delay option.
Regarding PayPal though, do they have any kind of setting that holds up the transactions that they are flagging? We're only going to fill the order if PayPal reports it to us as complete, so if this is activity that PayPal can spot then it should also be possible for them to delay the reporting to us, or at least require manual review on those transactions.