I do not work for Stripe and have no official affiliation other than the fact that I use it.
While I have not personally used Stripe Atlas, I do use Stripe for all my web apps, specifically my SaaS and pay-as-you-go invoicing.
Obviously, Stripe is a company that charges 2.9% + $0.30 so they are in it to make their own money while also providing something of great value to many companies and especially developers who had no other way to charge, but to use Paypal.
I've since released a few web apps into the wild and it has caught a fraud charge, while also processing many other legitimate ones, so in what it does, Stripe actually makes the whole process of charging, subscriptions, recurring payments, and even catching of fraudulent easy.
Pretty sure that they have your business interest as the heart of their own company goals because if you are successful in your business endeavors, they are obviously going to benefit from that as well.
And opening it up to places outside of the United States can only drive even more business for you and for them.