I am a fan of the Core i7 because of its power, but I do not like how hot it gets.
Fast CPU = Hot
High Clock Rate = Hot
Not all i7's were created equal.
Look at the CPU's TDP (Thermal Design Power).
Core i7-6920HQ This one is fast but runs hotter than this one: Core i7-6600U
The first is 45W and the second one is 15W. (TDP)
Personally, I'd rather deal with the heat than a slow computer.
Also, the heat produced by your laptop is also affected by a discrete graphics card if you have one.
If cool is really what you want then get one with intel graphics and a CPU with the name that ends with the letter U.