I feel that while the iPhone 6/6 Plus, overall, are the two best phones on the market for my needs, I agree with NIKKG. 2GBs RAM and 32GB base storage are overdue, especially for a phablet device that is going to be worked like a primary computer by many folks.
Maybe that's the problem. Macs are so good, I buy a MBP once every 5 years. Swap out the hard drive, add more RAM after 2-3 years and it's good to go for another round of use. They are great machines and no PC I've owned has the durability and lifespan of a Mac. Add 2 or more GBs to the iPhone 6 Plus and instead of swapping out every two years, I may go for three or more.
As for AT&T, I will be going to the Apple Store near my house, buying the model I want, and sign up with T-Mobile since I received the dreaded "Oh, hey, we're having problems filling your order so you're going to wait an for a week. Kthxbai." I'm guessing that's more an issue with AT&T's lack of supply chain management than Apple.