Just to circle back to that credit-building loan idea. I think that there's room for innovation still. Maybe instead of a low appreciation CD, it could be tax-free muni bonds? People, especially younger ones using the service see that securities can be a good investment (which is a service they can matriculate in to, especially with the increasing popularity of Robo-advisors) and their loan money is funding construction projects and stuff around the country. Build your credit...and America.
Making $100 per CD loan or whatever doesn't have a ton of margin, but then they're probably investing the income elsewhere like an insurance company.