The debit rates you are referencing are for in-person transactions where a pin number is entered. Debit cards can be used for online transactions but the interchange cost is more like 1.8% + $0.10.
Hopefully increasing the response time to > 2s (whether it's settable in the API or just has a longer timeout) is on the roadmap, I can think of lots of future use cases where you would want a human in the loop on authorizations.
Looks like a great product and props to you and your team for shipping this.
One of the concept mockups says patent pending. If the author is attempting to patent this I can see why he wants to re-open the established standard, but there isn't much value in changing how the buttons are arranged. And frankly, if he's trying to patent this button layout, it doesn't matter if it's any better because it will never be used due to the patent.
The future is more likely dialing by voice than it is a re-arranged button layout.
Voter registration data is available for purchase, but only by registered political committees and can't be used for commercial purposes. This also doesn't include a lot of the breached data like partial SS#'s and drivers license #'s. As a Chicagoan I'm not too happy about this breach, and there has been surprisingly little coverage of it locally.