Concerning the pricing, it's a freemium model based on the amount of Runs made. We offer 50 runs per month which approximately means 50 diagrams generated. We consider that a run is performed every time you modify your terraform files as we will process them to generate a new diagram.
Regarding the name Holori, despite we are french, the name actually sounds Italian and I personally love the italian language :) Also we wanted a name that sounded technological, fun and that could be pronounced worldwide!