Make the Cart Addon (book multiple services at a time) properly work with confirmation emails, generated invoices and .ics files

I let customers book a service and in turn they receive a confirmation email with the invoice and .ics calendar files. Now I want to make it possible for them to book multiple services as offered by the Cart Addon. While the booking process already works with this addon, it lacks proper integration with confirmation emails, invoices and .ics calendar files.

Please add functionality to insert a properly formatted list of apointments into emails, invoices and .ics files (for the latter, we probably have to send one file per service, that means multiple .ics files have to be appended to the email).

There already are some placeholders available for email and invoice, but I cannot make them work to have a nicely formatted list of appointments that I can customize, e.g. to put the elements in an html table and to select which appointment information should be depicted. Increased granularity in the placeholders is therefore required for email and invoice.

Also, please come up with an idea to solve the problem that we do not know how many items the customer purchased. To create a proper html table, e.g., it presumably is required to integrate some kind of loop functionality (looping over every item in the Cart whilst writing lines of email / invoice text).

I think only then the Cart Addon is actually of use.

Thank you!