I am wondering if blockstack would make sense as a platform for an app requiring large upfront investment. I am a bit confused about how someone might make money from an app built on blockstack. Are there apps that rely not on App Mining as a primary means of revenue, but rather direct payments from users for a subscription service?
If you can build an audience and build what is required for them. Definitely customers are ready to pay. Subscription service is possible. We did this for BlockSurvey(https://blocksurvey.io). Post app mining, we started charging customers and we currently have few paying customers now.