Why I'm wondering to switch to Canon after my experience with D600 + 24-70mm

With all due respect, you are wrong with your analysis on a number of things you said, but since you have the right to express your opinion and spend your money any way you wish, best of luck with the Canon brand. Until you have more experience at photography and better understand how the equipment is supposed to work, you'll likely be complaining about your gear no matter what brand it is.

glo