Well... if you knock the phone mostly due to its size.... that isn't the PHONE's fault. Look, how you view the Nexus 6 pretty much solely depends on your ability to deal with the dimensions. Taking size out of the equation, the thing is bloody brilliant.... But the size!
It's not like no one knows how big it is until they take it out of the box for the first time... ERMAHGERD! IT'S MASSIVE! No... if you buy the thing, then come to find that you can't comfortably manage its size, then get a smaller phone. I have big hands and when I saw it in a T-Mobile store and posted a pic, a couple of people thought I was holding the Moto X instead. I can one-hand the thing fairly well, but it does take a bit of a reach to do certain things (like getting to the status bar/notifications) with one hand and I use two just as often (but about as much as I did with my other, smaller phones). So I can respect the frustrations of someone with less ham-hock like appendages expecting to flick out emails and texts without issue. I mean, I'm counting the days until one of the custom roms add in the ability to add a custom nav button to drop down the status bar/notifications shade.... I had that on my G3 and it was legit.
For a lot of people, you'll have to use the Nexus 6 as a phone-enabled tablet. If you aren't prepared for that, don't get the phone.... but don't blast the thing for being large and then call it a mistake because you can't deal.