You, my friend, are one of the unluckiest members on this forum. I really hope you get a device one day that works as advertised!
When you say screen was on 2 hrs 5 min, 33% of battery usage, are you saying that 67% of battery was left after 2 hrs 5 min of screen time? Because that's not bad--that means you're on track for 6 hrs of screen-on time, which is pretty normal for average mixed use on a Nexus 7. But if you mean that your battery was almost depleted, and the screen was on 2 hrs 5 min, accounting for 33% of total battery usage, then that is abnormal.