Nice! I was going to point out the project I’ve been working on [1] to reduce the cost but I see you’ve already found it :-) Feel free to reach out it you run into any issues!
(Your build example says the tiles are 99GB, and their normal tier is $0.023/GB)
I guess the part of the cost that people actually care about is the bandwidth. How do you suggest dealing with that part of the problem?
There’s a python utility to convert mbtiles to pmtiles, but I’m also planning to add native pmtiles output to planetiler soon [2].