It is hard to get philosophy right--I mean the big picture. Plato, Aristotle, KANT are certainly on top and I would have to add Leonard Nelson --of the new Friesian School. BUT even Nelson needs a good deal of clarification as per the friesian.com  of Kelley Ross. However it is a huge mistake in philosophy to have run into the vast array of 20th century ridiculous vacuous pseudo philosophies. [However, I still think that Hegel is a worthy rival of even this Friesian modification of Kant.]  

I think it is too easy to be impressed with 20th century Analytic Philosophy-so as a cure for that disease i recommend Robert Hanna's  book on Analytic Philosophy's fall into the trash bin of history along with existentialism, Post Modernism, The Frankfurt School's neo Marxism. i do not claim to have studied all this thoroughly but i did read a lot of it. The flaws in all of it can take time to see but some are more obvious. It does become to people that are interested in ''big picture'' philosophy--to go back to the serious thinkers--not the superficial ones that sound profound.