I also miss a lot of information. How do you prevent ending up in spam boxes? Which templates to choose from? What can be configured, what not? Etc.
Also interesting insights / developer journeys like how easy Chargebee is for you as developer, etc. would give me some incentive to try it out. Just my two cents!
PS: 3 days ago https://news.ycombinator.com/item?id=19562539 it was a MVP and probably buggy. Maybe tell that to your customers as well. ;-)