I agree with you that education's value is in its signalling (I'm excited for you to read The Case Against Education). But signalling isn't 100% of the value of the education--maybe more like... 70%? hard to quantify--and I believe that's where there's room for ideas about what that education should consist of. After all, if we're gonna make them jump hoops for four years, they ought to be doing something socially useful during that time.
I like Pinker's articulation. It's concrete, for one (get out of here with that "the purpose of college is to find yourself." I don't like the federal government subsidizing something so vague). I agree it ought to impart humanism and intellectualism.