A couple things off the top of my head that I don't like now that I've put in about 1,300 miles or so on my 2016 CX-5 GT w/ tech & iActivesense:
1) For those with adaptive headlights, the AFS OFF button was moved to be a feature buried in the infotainment system. I don't really care whether there is a dedicated button for it or if it is buried in the infotainment system (since I don't press those buttons much anyways), but it seems silly that all of the other on/off buttons (such as for the lane departure warning, blind-spot monitoring, etc.) are on the left-side of the dash, and this one is not (though it used to be, and was apparently moved for 2016 for some reason). It seems to me they should have either moved ALL of the buttons to the infotainment system and used the empty space on the left-side of the dash for something else, or they should have just left the button there. Perhaps this is a pre-cursor to a future design change for 2017?
2) A bit more/better lighting in the interior would be nice. I'm thinking make the interior bulbs and license plate bulbs LEDs as a standard, add LED lighting to the cup holders, and offer optional LED lighting for the foot-wells.
3) No foot-activated power lift-gate. No trunk release on the key fob, either.
2016 Mazda CX-5 interior is still absolutely outstanding, though. The best I've seen in its class.