* You should figure out a way not to require the payer to choose a password. Especially if they're already choosing a password on my service, now they're choosing two passwords. I understand that you're using this to handle plan changes and cancellation.

* Allow people to sign up for "free" products, too. This could potentially allow people to completely delegate their pricing pages to you, and you could be involved in the upsell process.

* Allow some formatting in the plan description. Specifically, I want to list things, which looks difficult to parse with a bunch of commas.