The SV or SL heat pump is a real advantage in moderate climates like Oklahoma City. The navigation system also allows remote access via smart phone or computer to check status of car and start climate control. The charging and climate control timers in the navigation system also offer more programming flexibility than the timers in the dash display of the S. Since you probably won't be pushing daily range to the limit for a 24 kWh LEAF, I suggest you look for a 2015 SV or SL. There are reports on the forum of early capacity loss on the 30 kWh batteries while the "lizard" batteries in the 2015 seem to be doing better in hot climates. The 30 kWh batteries do have a longer capacity warranty so you would be covered for 8 years or 100,000 miles compared to the 5-year, 60,000-mile capacity warranty and 8-year, 100,000-mile defect warranty on the 24 kWh batteries. Keep in mind that warranty is from original in service date regardless of model year and manufacture date.
I personally would not pay $4,000 more for the 2016 S, but would pay that much extra for an SV or SL.