The poster mentions issues with Notes and Freeform. I use these apps with an Ipad Mini 6, and suffer from freezes, latency, high power draw and crashes. I was previously considering getting a more powerful device like an Ipad Pro, but according to OP this won't fix it at all. Paraphrasing a redditor, the Freeform app seems to have been developed as a demo tool to use in Apple Stores.

In theory, there should be some sort of paid app that uses all the incredible hardware for an actual good experience.