Worse thing I ever did was update to IOS 7. My 4S had no lag, stutters or stalls and IOS 7 put an end to that (as well as being butt fugly). Given the option, I would go back to IOS 6.1.2 rather than IOS 7.1 but it's an option I don't have.
In some ways I agree with the shocking changes when I decided to update my iPhone 5 from iOS 6 to iOS 7, as I was so used to the way things looked and worked and the craftsmanship in the older apps and also the "character" that made the iPhone what it was.
After using iOS 7 for a while, it really started growing on me. The look and performance improvements on newer iOS hardware. It does look more modern but more or less on white iPhones and late model iPod Touch as well as iPads.
Lots of white seemed to be part of the overall design and look of a white iPhone, iPad, etc. my problem is I have all black hardware so the change was a bit of a eyeball burner.
The technical side of all the use of light shades of white and such actually causes a less power draw on the battery since black uses the most power draw on a LCD display when the opposite is the issue with OLED screens.
So we did by a slight bonus, get a bit better battery life. The overall look and feel of iOS 7 will grow on you once you spend some time using it. Going back and working with my 4th gen iPod Touch with 6.1.2 on it almost feels like picking up a much older iPhone.