Edit: tried to make question clearer to solicit some replies.
What is the first 20% of striking or throwing stuff that gives a beginner 80% of benefit? What is the minimal stuff I should study?
For example:
Striking: I think johnwang's rhino guard is a great start here, but what else would you recommend?
Throwing: Cartmell's classifications: arc, circle, spiral (movement of the person being thrown) are really helpful to me. Learning only a few throws like a hip throw, a leg reaping throw, a diagonal fly type throw, and maybe a single or double leg takedown seems like a good enough start.
Usually in a given activity, beginners need this first 20%. Intermediates work on many detailed variations. Experts are phenomenal at the basics and might mainly use the first 20% (but done extremely well). Lionel Messi for example keeps it simple but is just insanely good. Throwing experts like Fedor or Rousey must know 100s of throws, but usually use a limited variety of throws in mma.