[joering2]

"Every question a user has to ask themselves during the checkout process is another reason for them not to complete it."

It depends what you are trying to sell. If you have used all known tricks to convince user to buy "lose 50 pounds in 2-weeks" product, then yes unusually good looking CC form nothing circa 97 can discourage user from converting. On the other hands, many times you offer product that user truly wants, and when your checkout is broken, they will send you a long explaining email, showing you how far they would go to get what they want.

>Beyond that it has to load images dynamically based on card type which on a slow or interrupted connection

I noticed that too, but thats mostly because this post > 420 upvotes. All you have to do is load them all in div style = "display: none" on body onload and viola! all are preloaded and hidden, waiting for your browser to use one from your cache.