So indulge me for a moment since I've only had iOS7 for about a week. Some things I've noticed...using the same wifi and same LTE coverage as iOS6 but I've noticed lag in webpages loading, with iOS6 webpages would load almost instantaneous now with iOS7 they added a progress bar at the top...this is bad because now I am looking at the progress bar and waiting for webpages to load and adding to the fact that it's slower. I remember when I first got my iphone 5 and saying wow LTE is so fast it loads faster than my wifi. But with iOS7 it is noticably slower.
My ways of dealing with all the bright/white....I am always using private mode when browsing the web, on my black phone it just looks so much better...I guess this is the best it will get regarding a darker theme. For my wallpaper I picked a photo I took that has a darker theme so that helps with less white. I still hate the photo gallery and music app that still uses this bright white background.
I'm begining to believe that the reason I am getting slightly better battery life is because I am forced to turn the brightness level down to about 40% on daily use while I was using about 60% on iOS6.
I also think with all the changes they made to the camera app going from iOS6 to iOS7 I have noticed with iOS7 it uses much much more battery just using the app. It seems the picture are better quality but at the sacrifice of battery.