Citi cards had this for a while, but got rid of it. It was quite nice, but needs more organization. Also the paypal model has it right. Even though I, like many others, loath paypal, I've been using them everywhere just to save time entering my CC. This doubles as security as merchant never get your CC in the first place.

Apple pay will probably fix the organization of the random CC # generation. Final seems to be a little late in the game.