If I may add my own comments here:
1. you should go to note 3 ATT forum and there find proper method to root your phone, we have towelroot program that can root phone very easily without breaking knox warranty, albeit I don't know if it works on your version, it worked perfectly on mine (t-mo)
2. While it is true that root by itself won't do anything about your battery usage, many programs that really help need root
For example greenify, titanium backup or android assistant require root to disable many useless (useless for you that is) programs that drain your battery
3. I totally disagree with Nitrous that GPS is the culprit for high battery usage. It is my experience that GPS all by itself does not work at all unless the location info is requested by some other programs. Google maps for example only run GPS when screen is on, when screen is off, GPS is off also. However some badly behaving programs can keep requesting location even in the middle of night, but IMO those programs are the problem, not GPS itself. I have GPS, BT and WiFi on 24/7 and with light use my phone could last 4-5 days. If GPS was draining battery as many people think, phone would never last that long.
What you should do is go to ATT forum and find towelroot method, root your phone and freeze, or disable apps you don't use. For example I don't use Bloomberg, Yahoo, Facebook, Hangouts, indexing etc (your list may be different, since different provider) so I have them frozen (won't start up) . If I ever change my mind, I can unfreeze them later.
You can also run programs to tell you which apps use most battery, or wake the phone from sleep and then decide if you need them or not.
BTW sometimes full reset and cache clear can fix some of the problems, so maybe that should be the first step.
Once you find which program /s cause problems your phone should last whole day. I could easily get 6 or more screen hours on my Note3, unless playing some intensive games, so should you and it just took couple hours to identify and disable all the bloat and there is a lot.
I also experienced increase in battery usage after updating to KK, but I have not found a time to look over the bloat and redo my program freezing efforts yet.