Order cancel facility on the orders page.
A facility to allow an order to be cancelled after initial submission before the job is manufactured. Once in manufacture and after payment, the facility should be withdrawn.
Mario Oravec commented
I strongly agree with this suggestion, I have actually wanted to cancel an order before pay and have to ask manufacturer to did so, He was offended to me and to cancel note he wrote "I would not recommend that user". In prototyping phase, I would say it is normal, an everything changing fast, why not my order decisions can do before pay or better before print.