receipt for payment?

If an event is paying and a customer registers and pays in advance, I would expect the system to be able to send a formal receipt for payment. I realize that qem is not a full-blown e-commerce system. However, the generic email that is sent confirming registration contains various types of information, but not the important data. Perhaps some changes in a future version of qem must be envisioned.
1) Why include the email address of the customer when it is obvious from the fact that the email message has been received at that address? What value is this in a message to a customer?
2) Likewise for the customer’s telephone number
3) The inclusion of the label for the checkbox for registering without paying is a mystery to me. What is the logic is putting this in the confirmation email? The label in the registration form needs to say something like, “check this box if you intend to pay at the door” (or the like), whereas the message in the confirmation email needs to say something like, “You must pay $10 at the door”. Two different texts, each with a different purpose.
4) If the customer has paid via PayPal, the confirmation message needs to confirm that payment has been made, giving the currency symbol and the amount paid.
5) The date/time of payment is quite important
6) A receipt needs to show to whom the payment was made, as well as the address.
7) I would think that a confirmation email would indicate the venue and address of the event, and not depend exclusively on the URL of the event for that information.