Reports of Google's decline are greatly exaggerated :) G+ is annoying, but these days no large company can make all their users happy, with all their products/features/changes, all the time. The so-called erosion of 'Don't be evil' has just become more apparent now, but as long as I have known google, they always made money from ads - and ads are fundamentally evil (IMHO).
Search, maps, email etc are quite nice and I use those everyday. Fast, reliable, solid products - vastly improved since I first used them (many years ago). Where is the decline?