6P is identical to the 6S+. Maybe less than 1 cm taller. Smaller bezels are always nice, but so are front facing stereo speakers. And a bit of bezel makes it easier to hold a big phone, especially in landscape.
I'm not arguing for or against the size...I personally have no problem with it as my other phone is a 6s+. I'm just making reference to previous comments severely critical of the size/bezels of the 6s+ yet the 6P has, as you pointed out, nearly identical dimensions.