How many stripe merchants have dynamic billing descriptors enabled, or the equivalent of dynamic billing descriptor equivalents with on POS systems?

There are a couple that comes to mind. Check out Paddle.

Most payment processors on the internet have a Recurring Billing option to bill for a specific interval for a specific recurrence count. I recall Authorized.net specifically does it and can meet PCI compliance. Most processors offer recurring option but may not provide a daily option. You may need to a custom solution such as Authorized.net Customer Information Manager (CIM) for dynamic recurring billing (you bill your customers different amounts or on different days each month).

I don't think there's a best practice, similar to how much you should charge for your B2B SaaS company, cause it really depends on the market size, cost to deliver, and perceived monetary value you're offering via your API. That being said, the way I've baselined any pricing for my products has been to look at 100 companies that share similar customers and pricing model and either look on their website or email their sales team and ask directly. Even if you get 10% response that's enough to get you started.

Where? The world is a big place. Short answer, conferences are not that useful unless you are on a panel/speaking etc. Recommend you focus on building grass roots. Conferences can be a part of it, but how you do conferences matters, otherwise is an expensive use of cash.

Hello, I believe that you may be over-complicating this a little. Typically, you need to have either citizenship or some other legal presence within a country to open a checking account within it. I would recommend establishing accounts in your own country first and then using ATMs in other countries to withdraw money, as "wiring" money internationally can be expensive. If you just need to pay for expenses while abroad, look instead into using credit cards that have no foreign transactions fees such as the Capital One Venture Card. If you really need accounts in multiple countries, you will likely need to incorporate within them. As for accepting payments in different currencies. Your best bet will probably be 2Checkout or Stripe Atlas to start. Stripe Atlas will probably have lower fees but will take more technical expertise to get up and running. Best of luck to you!