Sounds like you would make a good mathematician.

I had a very similar reaction to the much vaunted 'Algorithm Design Manual'. It was all fluff with not much substance.

I found http://jeffe.cs.illinois.edu/teaching/algorithms/ pretty good for an overview over Algorithms.

If you like something in a similar vein to TAOCP, the book 'Combinatorial Optimization' by Alexander Schrijver fits the bill. It teaches you everything you ever wanted to know and then some on the mathematics behind problems in P. Just like TAOCP it is also a detailed overview over known results. See https://homepages.cwi.nl/~lex/files/book.pdf for the list of contents.