What's jarring to me is whenever I see the repulsive "iOS 7 look" creep into 3rd-party apps that until then looked perfectly fine, but now are hideous to look at.

I still use my iPad 1, running iOS 5, on a daily basis, and I find the old iOS look infinitely preferable -- anything
but "old-fashioned". It's better to be old-fashioned than ugly.
A big reason for me to be considering a switch away from iOS to Android is how ugly iOS 7 is; it has, for me, significantly decreased the attractiveness of the idea of getting an iPad mini, for example. The device no longer seems as desirable as when it was running iOS 6.