Definitely agree about prompts -- for MedQA [0] I ended up building up a prompt around 300 words long to get a collection of results I was aiming for. I'm still not sure about the best way to go about building a "stable" lengthy prompt that can maintain a predictable output even after adding to it; my approach was mainly via trial-and-error experimentation.

[0] https://labs.cactiml.com/medqa