hi - I decided not to post the entire list in that bulleted list because it would be too long but I can assure you I did look into a lot of providers including Chase - I plan to post about all of that in another post hopefully next week. Thanks for reading the post and giving me your feedback.
I think one of the big factors in going with Stripe over PP Payments Pro was the strong technical side that Stripe offers.
Interestingly, that is the reason I would go with PayPal over Stripe. Stripe's API is touted as "awesome", but I see no way to automatically reconcile chargebacks (the word "chargeback" isn't even present in their API documentation), and their "webhooks" feature is explicitly missing the critical functionality of "retry if the server failed the response" (making it totally useless to rely on: you are going to have to drop to polling to trust your data). I would thereby additionally be very curious to know what technical factors you found lacking with PayPal in relation to Stripe.
Is there a traditional merchant account provider that has an API for chargebacks? I've actually never come across that anywhere but PayPal; maybe it's more common with 3rd party providers since they already need to connect chargebacks with their online service just to attribute the fees to the right user.
The other service I have been looking a lot at recently is Litle & Co, which has even better chargeback support than PayPal: they offer the ability to not just reconcile but fully automatically respond to chargebacks, complete with APIs for uploading documentation such as shipping invoices.
I do not know if you (or anyone) would count them as a "traditional merchant account provider", however (or if they are really a "merchant account provider" at all; I will be honest and say I'm still behind on some of these terms).
(Also, for completeness: Amazon Flexible Payments, in a similar boat to PayPal and thereby falling under the same "already need" reason you list, also has good mechanisms for automatic chargeback reconciliation and reporting.)
The payments space gets confusing. There are gateway providers that serve merchants yet process payments through an underlying provider. At the end of the day there are multiple types of companies which can serve your needs.
I am bias since I work at Litle & Co. My team implemented the chargeback upload API years back, it's great to see it catching on.
Litle has some neat features including a JavaScript API for tokenization that we call Pay Page.
I won't go on self promoting, however I can answer questions if you have them. I follow hacker news because of my personal interest in software development.
I think one of the big factors in going with Stripe over PP Payments Pro was the strong technical side that Stripe offers.