Looking for a system that makes it as easy to refund money just as it allows purchases. This will greatly reduce inconveniences that come from fraudulent purchases or purchases made on your own but decided to renege later. I don't like the whole asymmetry of instant payments and waiting several days to process refunds.

Also the payment system must be able to link to bank accounts (retaining the same swiftness to update balances via refunds), and not use cryptocurrency. What payment systems would fit this criteria?