An additional setting you may want to consider... not using. In the App Store, there is a new item; "Install OS X updates". I had that enabled in the Beta, along with the other three (older) items, just to see if I encountered any problems. I will not have any of those items enabled when I finally get around to installing
Yosemite on my main Mac. Aout the only one I'm tempted to enable is the "Download new updates..." item. I'm still not ready to allow automatic
installs of
anything, even from Apple, until I make a backup of the current version... YMMV, of course.