Stripe just does the processing. But for SaaS, you really need something like https://bullettrain.co/. It does pricing pages, subscription and user management (which is what takes most of the time to implement).
Don’t forget the topic of revenue recognition in SaaS. Basically, you need to allocate your revenues per month if you accept yearly payments. Also, you need to consider up/cross-sells and cancellations, that drive up complexity. I have seen SaaS companies using excel for this...
This looks really interesting. Are there alternatives that are built on other frameworks?