It really is only a guess, but, for what it is worth, the Chernev book might be the next thing to read completely. Sometime soon, it would probably be a good idea to read in the Silman Endgame book up to the point indicated by Silman in the book itself.
Which chess book should I read next? (There's a catch!)

The Most Instructive Games of Chess Ever Played, by Chernev.
It's always the book I recommend first to players who know the basics of the game but are actively looking to improve.
My thanks to each of you: ylblai2, Bawker, and Moxieman for your recommendations! I think I may opt for the section of the Silman book for my rating, and then switch to Chernev for a while. But I do want to get to The Art of Attack eventually!

You can also add to your list
1. My Systems By Nimzowitsch
2.Think Like A GM by Victor Kochnoi
3. Play like a GM by Victor Kochnoi
4.Tactics for Champions by Suzan Polga (you can also check our her father's books on tactics , Laszlo Polga
5.You should prolly get any end game manual from authored / based on strong end game players

It looks to me that you have 19 books already. My guess is that at a rating of 1600, there's probably tons of things in the books you already have that you could/need to work on.
Another thing I heard was, "If you're not happy with the stuff you already have, what are the chances getting more stuff will make you happy?
Just my .03

You can also add to your list
1. My Systems By Nimzowitsch
2.Think Like A GM by Victor Kochnoi
3. Play like a GM by Victor Kochnoi
4.Tactics for Champions by Suzan Polga (you can also check our her father's books on tactics , Laszlo Polga
5.You should prolly get any end game manual from authored / based on strong end game players
Don't forget Chess Praxis my Nimzowitsch!

"Pandolfini's Endgame Course" - errata
http://www.glennwilson.com/chess/books/pec_errata.html
(While there are more typos in the book than one might like or expect, claiming 200+ is hyperbole)
Thank you, Fhumu_Mo and AiryNeon. I was actually hoping someone might suggest other books, too, though the fact remains that I want to read the ones I have. Any new books will likely not get either purchased or read for over a year (with one exception I haven't mentioned).
--
Thanks for your comment, too, oneshotveth, even if it is quite redundant. I made clear in the very first sentence that I was looking for recommendations among the books I already own. I believe I have some good books, and I am quite happy with everything I've seen so far, except the Heisman book (though it may be that I wasn't ready for it, I'll admit), and the Pandolfini book (this last, due to the multiple errors).
--
Thanks, redtrucker, for your advice. Actually, I believe that lack of board visualization skills is my single biggest weakness. There's no doubt I need to work on that, plus a number of other things!
--
RussBell, regarding my comment about Pandolfini's book containing 200+ errors, you're absolutely right, and I'm wrong. I actually had already visited the site that you so kindly linked to, and I simply hit "end" on my keyboard, and used the number of the exercise as a total, not realizing that the last number was simply an exercise or page number. Perhaps I made the same mistake with his page that oneshotveth might have made with my post (so now he has my company to enjoy). Nevertheless, the nearly 40 errors in that one small book render me sufficiently annoyed. Where was the editor?

You problem is not which book to read but any book you open you should play it!
You learn more if you play it than just reading it and you also imbed it in your brain.
I M H O
DENVER

You can also add to your list
1. Winning Chess : Pieces by Pieces
2. Learn from Garry Kasparov's Greatest Games
3. The Art of Chess
What book to buy really depends upon what you feel you need to get better at. Here you can get the nice collection of books if you need to improve your overall game. Chess Tactics for Champion is also a must read book.
http://www.chessbazaar.com/chess-set-accessories/chess-books.html?dir=desc&order=price
The catch is: it needs to be a chess book that I already own! Here on chess.com, I'm about 1600 in 30 minute-per-side chess and 1400 (at the moment--I oscillate between 1400 to 1300) in 10 minute chess.
Someone once said that for a lot of us patzers, the number of chess books we have is inversely proportional to our ability to play. That's certainly true for me. I actually used to have many more chess books (I was lucky enough to get many on a fantastic sale, but I sold many of them, too.) Anyway, after decades of books sitting on my shelves gathering dust, I've been making a concerted effort to read some of them. Except for the second item below, I've read the following books cover to cover in the last few months:
As a young teen, I also read many chapters from I.A. Horowitz's How to Win in the Chess Openings, and Modern Ideas in the Chess Openings. Unfortunately, I have made next to no effort to memorize opening moves in almost any opening. This is something I should definitely work on, of course.
Now, the rest of the books I own, including two more that will arrive tomorrow, and a few that I got from my dad twenty years ago:
Incidentally, for tactics, I use the Chess Tactics for Beginners App for my android phone. I've seen, if not solved, all the exercises, and am cycling through again.
I have no doubt that I need to work on every phase of my game, but my biggest fault is actually hanging pieces--this usually happens in 10 minute games when I'm either in public transit or nodding off to sleep in front of my laptop. I'm going to try to take Silman's advice to heart to address that.