Really great breakdown! Another important thing to think about when building out a production or even dev environment are the other associated costs (i.e. bandwidth, storage, egress, etc). We think that these costs can be pretty obscene in the public cloud and we try to optimize as much as possible to keep the total cost down.

Disclosure: I'm one of the founders of Paperspace (https://www.paperspace.com) and we spend a lot of time thinking about GPU compute and pricing. Happy to answer any questions here