Configurable invoice and packingslip:
I would really need the ability to add/configure/define information fields freely, similar to a "form" under "Content>>Pages".

In Norway, when the client is a registered company, invoices are sometimes sent together with shipment for payment withing 30 days (or similar). This generates the need to provide invoices with info like bank account number, IBAN/SWIFT information, Company/Organisation Register Number, payment deadlines, client contact, client reference number, and custom text, and even possibly advertisement of a similar product the client bought.

Thanks for a great shopping cart!