Totally agree. I stopped reading them after the first few as well. The books turned into introspective political musings, with no action at all anymore. Super boring.
It's a rare book series that can go beyond 3 to 5 books and still stay interesting and maintain good quality.
I think I read 8 or 9 of them (still have them on bookshelf somewhere) before I looked at my wife and told her “that is 24 hours of my life I won’t get back.” She still laughs at me over that remark.
The three book series seem to be the best of the fantasy genre more often than not and there are some good ones out there.