Temp wise, you're in a great range. I wouldn't worry about 60 to 70 unless it changes very fast. Over the course of a day, you're ok. Steadier is always better.
Temps under 60, you could lose oils faster. And your humidity will drop as well. In the summer, when my wineador is turned on, it's pegged at 66. In the winter it fluctuates with room temp. Ideally I'd keep it at 70, but 66 is as high as it goes, and I have not installed additional equipment to change that (though many handy guys here do).
The real danger with temperature is anything over 75. If tobacco beetles are present in the cigars, they can hatch in that heat, and you have a big problem.