Alright so after extensive research on cases here's what I settled on: Spigen Exact Fit for every day use (minimal size and protection) and the Vena Kickstand Case for travel / if I'm getting drunk lol. I read the spigen air cusion kickstand was flimsy and I really like the kickstand on the vena.

Also consider the Spigen Exact Fit. It's slim like it sounds like you're interested in, but doesn't have the added bulk or "squish" that TPU cases like the Diztronic's have.

The Diztronic is great for drops on hard surfaces. Charging port was a bit odd too with the stock cable or any USB cable slightly oversized.

I hate to rag on the Diztronic but there's more. There's no dimple cutout with the Diztronic Full Matte TPU, and the camera cutout is slightly larger than the camera itself which makes it look kinda odd to me.

I like the Spigen Exact Fit because it adds grip, little bulk, and full port access. It's a "shell" style case and would only protect in the smallest of drops. http://www.amazon.com/Spigen%C2%AE-Exact-Fit-Smooth-Premium-Finish/dp/B00OH4HLJ8

I got the 2015 Nexus 6 two weeks ago (the one on Amazon for $350 right now); actually I got the 64GB version for $400 (before tax) and I love it. I think its a better deal than either the 5x or the 6P because you can get more space for the same price or less. I don't really see the difference in specs being as worthwhile as more space, but thats just me. Also I love the size. Though it helps if you get a case with a cut-out for the logo and some kind of matte texture, I got this one and its working well. Otherwise the phone is a bit slippery to hold due to size and thinness.