My personal experience has been that the simpler undergrad algorithms are the most applicable. That’s probably also why you learn them first.

IMO, it’s much more practical to thoroughly learn and understand the simpler techniques. There is often more depth to it, than you’d think.

Analogy: Many (most?) MMA matches are won with techniques you learn in the first year.

Aside: I’ve gotten much more mileage out of simple statistics in the 16 years since I graduated, than advanced algorithms.

EDIT:

IMO, theories and techniques can be easy enough to learn. Figuring out applications can be much more difficult. It requires some creativity.