when you say throttle, do you mean get very hot because it's a single fan solution!? Well yes, the mini's get hot. But the fan will do the trick and keep it within parameters. If OC'ing though you'll really wanna watch the temps, or it may throttle or have artifacts or game crashes.
If you are playing at 1080p 60hz, the GTX1060 6gb is a perfect fit. For nearly every game out there it will hit ultra settings with steady 60+ FPS.
What are you other system specs? If for example you had 8gb of ram, i'd get the 1060 and get some more ram.
The GTX1070 is about 10-20% better FPS than the 1060. Game dependent of course.