In terms of conversions, the general rule of thumb is the less clicks the better. With that in mind, it may be a smoother flow to pre-select the Ethereum payment method by default during checkout after choosing to register an available name. Most users will be paying by Ethereum, and personally we have found that having to click the Ethereum payment radio button, and then having to click on next has slowed down the process of registering a name.
Also, it would be cool to have an FAQ link about “Paying with a Credit or Debit card but I don’t have an Ethereum wallet yet, why I need a wallet, how to get one, and what do I do after I get a wallet? (come back here and click connect, find your available name, choose credit or debit card…” which would include some other newbie helpful tips and explanations.