Learn from the Legends: Chess Champions at their Best, by Mihail Marin
https://web.archive.org/web/20140708233457/http://www.chesscafe.com/text/review500.pdf
Chess Secrets: The Giants of Strategy: Learn From Kramnik, Karpov, Petrosian, Capablanca And Nimzowitsch
https://web.archive.org/web/20140708092313/http://www.chesscafe.com/text/review620.pdf
Chess Secrets: The Giants of Power Play, both by Neil McDonald
https://web.archive.org/web/20140708112104/http://www.chesscafe.com/text/review711.pdf
The Improving Chess Thinker, by Dan Heisman
https://web.archive.org/web/20140708101955/http://www.chesscafe.com/text/review717.pdf
Secrets of Modern Chess Strategy, by John Watson
https://web.archive.org/web/20140708094414/http://www.chesscafe.com/text/smcs.pdf
How to Defend in Chess, by Colin Crouch
http://theweekinchess.com/john-watson-reviews/testifying-for-the-defence
http://dev.jeremysilman.com/shop/pc/How-to-Defend-in-Chess-p3510.htm
https://web.archive.org/web/20140708104148/http://www.chesscafe.com/text/howtodefend.pdf
Van Perlo's Endgame Tactics: A Comprehensive Guide to the Sunny Side of Chess Endgames, by Ger Van Perlo
http://www.jeremysilman.com/shop/pc/Van-Perlos-Endgame-Tactics-78p3851.htm
http://theweekinchess.com/john-watson-reviews/theres-an-end-to-it-all
https://web.archive.org/web/20140708234128/http://www.chesscafe.com/text/review555.pdf


I am looking for books mostly to improve my game, particularly strategy and positional play in the middle game. I already own a couple of openings books, Silman's HTRYC/Amateur's Mind and a few games collections, including Tal's and Fischer's (I own about a dozen books in total). What do you think of these books on my wish list?
Learn from the Legends: Chess Champions at their Best, by Mihail Marin
Chess Secrets: The Giants of Strategy: Learn From Kramnik, Karpov, Petrosian, Capablanca And Nimzowitsch
AND
Chess Secrets: The Giants of Power Play, both by Neil McDonald
The Improving Chess Thinker, by Dan Heisman
Secrets of Modern Chess Strategy, by John Watson
(I already have Watson's first Mastering the Openings volume. He seems like a really great writer!)
How to Defend in Chess, by Colin Crouch
Van Perlo's Endgame Tactics: A Comprehensive Guide to the Sunny Side of Chess Endgames, by Ger Van Perlo
From the reviews on Amazon, all of the above seem like high quality/top notch books. Some have won major awards.
What do you think of them? Are they instructive? Well-written? Mostly prose or reams of variations/analyses?
Anything else you can recommend from this genre? I am looking for books of intermediate to (somewhat) advanced level. And I want to steer clear of books for beginners or for masters and above. And if any of these or other books have too much variations/analyses, I'd rather steer clear of those as well.
THANKS and much appreciated!