I did the same thing... I had both a 2012 and 2103 and I gave my 2012 to my nephew and sold the 2013. I ended up purchasing the iPad Air and I enjoy it so much more. I spent so much time trying to get things to work on the Nexus 7. Swapping kernels, rooting, etc. games and certain apps didn't work well on the smaller screen. Fonts and other UI elements didn't work right. I didn't like Android, and as much as I appreciate the flexibility and openness the over all experience sucked.
There are so many more apps on iOS that look and feel better on the iPad vs Android on the Nexus 7... It was very annoying to see horrible UI phone elements on the 7" screen. Again, this is a direct comparison between both of the devices and their respective apps.
The Android apps I used were also slower on updates and clunkier than their iOS versions. Overall, it just fell short of a desirable user experience.