Problem with PayPal is that they ban people (I lost my account years back, still do not know why) and also of course not available in all countries.
I was thinking something along the lines of some sort of new HTML "payment" tag so it could signal to the browser things such as "product details, price, available/preferred merchant payment method"
and then the browser would pay from an in browser wallet containing stored credit card numbers, or bitcoins or prepaid/voucher codes, or bank account information
Some browsers could outsource this by starting a separate wallet program altogether, sort of how some links on mobiles open up other apps like maps
Someone above mentioned bitcoin links, that be a very good example of how to do UI payment flow nicely, especially nowadays that
Eitherway I think credit card forms are anything but user friendly, even the cleanest of forms such as Stripe would dumbfound new internet users such as my mother who rightly asked before "is it safe for me to be entering my cardcode on the internet"
Pre-filled credit card information would be great - if it could be stored securely. PCs are basically far too insecure for this to be accepted by the payment processors, it would just be phished to death.
Apple Pay would be the right solution if it weren't so proprietary.
Apple Pay uses industry standard payment tokens, just like Google Wallet, there is nothing stopping any company out there from using the technology. The only thing about Apple Pay that is proprietary is the TouchID fingerprint verification.