I have exactly the same issue - since going to 4.4.2. Battery usage was great in 4.3 - but since going to 4.4 it was awful (android system using 30% of the battery overnight).
I did a factory reset - which kept me at 4.4 but uninstalled all my apps etc (and put google play services back to the original version). I then turned off location services altogether (I had tried battery saver, but it made no difference). Since then I have been having little or no issues - android system is hardly using thing overnight. Google play services has updated back to the latest version.
So it is defo to do with location services and/or some app using it to death - haven't risked turning it back on yet - but will do - might go for gps only first, then battery saver (which did no good last time). Google now is currently off - but I may turn it back on as part of my testing