You're completely right.  Walt Jr. is like the abstract idea of a son.  All the passion, all the life, is in Walt's relationship with Jesse.

More money than anyone could spend in a lifetime.  So, what was the point?

I agree that Walt's attachment to Jesse, maybe even more than his attachment to his wife and kids, represents the human side of him.  It would take a whole lot, though, for him to come out of hiding so openly ("Hello, Carol") just for that…