The key takeaway seems to be that their whole pricing scheme is based on customer and potential customer feedback. Interesting that they did not mention the competitive landscape and pricing schemes of others.
Externally I'd say the community on IndieHackers has been a big help.
Second, but this came back to bite me, I asked many of my closest "colleagues" about their thoughts on pricing. All consultants within software development, which is generally priced higher than the broad average of freelancers - And this isn't intended specifically for developers, but anyone who's starting out.
A finally reading everything I could find online, like https://www.cobloom.com/blog/saas-pricing-models# - But as you can see ultimately we didn't follow these strategies too closely.