I don’t agree at all with the idea that one should necessarily just stick to certain “stock” teachings. For me, some of the most useful suttas are ones I haven’t seen emphasized, and I only learned about from just reading through the Nikayas myself.
Tbh I haven’t gotten a lot of mileage out of the Satipatthana sutta (I prefer the Satipatthana Samyutta), the Anapasati sutta, or the cardinal discourses.
Other people are different, of course. Heck, there’s a great thread going on right now about 1-2 liners that summarize the whole path….maybe for some people just focusing on one of these quotes is enough!