This is a decent idea - I've always had the idea of a payment processor that would give low spreads and work on popular online sites like Amazon, eBay, etc.
I believe this could work - purse.io comes to mind for a really popular app and it's the only one out there which allows you to pay for Amazon with your crypto-currencies, works pretty well but the rates are pretty shitty.
Good luck op, this project has a real use.
Appreciate the kind words. Paxful and purse are both inspirations for our idea as we are users of both. However there are few improvements we believe that can be made.
One of the improvements is to automate the process and make the user experience feel native as if you can purchasing directly from the merchants instead of on a third party platform. As one of the biggest issues we had when using the other platforms was the overhead time spent on chatting with counter parties, disputes, and going back and forth between merchants and the crypto paying platform.
We are also looking to expand the variety of products that can be purchased using crypto, and expand into every day services such as Airbnb, Uber, and Ubereats.