I'm curious, how did you determine that the problem is iOS 7, as opposed to your hardware – or, perhaps, the need for your hardware's power management needing to be reset/recalibrated?
I only ask because I recall reading some complaints during the beta cycle that were resolved in some way without changing the specific version of the pre-release they were running.
It was a very clear change for me. I'm usually at work from 7 to 5. On iOS 6, my iPhone 5 had no problem making it through with moderate use. There were no jumps in percentages. I could use the phone for an entire hour with <10% remaining.
Once I downloaded the beta, I found myself with a dead phone at noon, having to fully recharge it at least once just to have a usable phone by the end of the work day. And I think I've only seen it actually hit <5% all of two times. It'll power down way before it gets that low.
I guess what I'm suggesting is that maybe the act of applying the beta to your phone put your power management hardware in a state that necessitates recalibration or reset.
For example:
"The issue with the battery drain on iPhone 4S was big and we saw the battery drain down in hours. However if you clean install first and then restore data, the issue doesn’t seem to occur."
I only ask because I recall reading some complaints during the beta cycle that were resolved in some way without changing the specific version of the pre-release they were running.