Add per-server payment methods
It would be great to have the option to specify payment methods on a per-server basis. This way, I could allow clients to pay for their own server without having to transfer the server to a client account. Most of my clients don't understand, or care to learn, about having their own account. They just want to pay and have me take care of the details.
Ideally, I could establish a default payment method for all servers on my account and then override payment information for individual servers as needed.