Let's see...
1) The overall styling. Whether it's the lines, the LED headlights/tail lights, the awesome 19" wheels, the kick-ass parchment white/black interior, or even just the red paint I chose, the styling is NO QUESTION the best in its class. I can't even begin to mention all of the comments I've gotten about what a good-looking car it is. It feels like I'm driving a luxury car, and although I know it's not a luxury car, it's not far off.
2) Safety features. Yes, I'm boring this way, but I love the blind-spot monitoring, rear-view camera, and rear cross-traffic alert that come with the options I chose, just to name a few. It's not a self-driving car by any means, but having these types of features available in this car's class and price-range definitely put my mind at ease.
3) Infotainment system. This one's the best in its CUV class as well, the controls are great and the screen is great, the system is easy to use, and it's a huge improvement over the old system. Would've preferred the tacked-on tablet look, but that's just a very minor quibble.
4) Excellent MPG. I still can't get over how they managed to improve the MPG on the CX-5 a couple years ago without sacrificing any of the performance.
5) Excellent handling. Also best-in-class. No other CUVs even come close. My CX-5 is a blast to drive, even though the roads around here are crap.
6) Excellent transmission. Again, best-in-class IMO (are you seeing a trend here?). Very, very smooth gear shifts and while the sport mode isn't a game-changer, it's still a lot more useful/better than the other sport modes I've seen in other CUVs.
7) Interior layout is logical. It's been a long time since I've had a car that had an interior layout that I didn't like, but there's nothing worse than wishing your cup-holder or nav screen was closer.
8) Seating position is great. A perfect fit for me, and I'm 6'2" tall.
9) Large on the inside, but small on the outside. This vehicle fits into some tight spots, yet still feels very spacious inside, has plenty of storage space, and lots of headroom in both the front and rear of the vehicle.
10) Again, somehow Mazda managed to accomplish all of the improvements they've made to this vehicle that was already an excellent car without sacrificing the vehicle's performance. Sure, I would prefer a turbo and a bit more HP, but the performance is right on-par with all of the other vehicles in its class. This, above all else, may by Mazda's greatest achievement for this vehicle.
Dislikes... only one. Where's the foot-activated power rear lift-gate with a trunk release on the key fob? This seems like something that should at least be optional. Maybe next year's model will have it, but it feels like this car should have it.
Everything else that would even remotely constitute a complaint for me is really just wishful thinking, like having a panoramic sun-roof, a good heads-up display, a power seat on the passenger side, or power folding mirrors. But, these are all minor things that aren't really complaints, just stuff that I would want if I could have the "perfect" car. Otherwise, I love my car!