Honestly, the credit card processor is going to be the real limiting factor. They obviously won't permit anything illegal, but there are also going to be whole

Honestly, the credit card processor is going to be the real limiting factor. They obviously won't permit anything illegal, but there are also going to be whole categories of legal-but-risky services that they won't allow either. If I'm correct in understanding that OP is using Stripe, they've got a whole page of things they won't deal with: https://stripe.com/restricted-businesses https://stripe.com/restricted-businesses