You're never going to find a definite answer regarding anything in training or nutrition. Lots of different stuff works. It comes down to trial and error, and eventually determining what works best for you.
Depends on multiple factors. Your age, current condition, experience, nutrition, recovery, goals, etc. It also depends on the particular plan. "Templates" are usually, by definition, more flexible than specific programs (like a 12-week arm specialization).
Something like 5/3/1 is a template designed to essentially avoid plateaus, with the regular deloads, focus on long-term projections, and short-term challenges. So that might be something to consider. Something like Starting Strength is a much more concrete program that's very much not meant for extremely long-term progress.
Okay, talk this one through. Where would you put Olympic lifts in the tried and true template you posted? What exercises on what days and for what sets and reps? Also, and most importantly, why? Why Olympic lifts and why those sets/reps?
That's a very common way to progress, yes.