I've got the 64Gn OnePlus One and am very happy with the phone and the performance. There's plenty you can do to tweak the camera experience and you can even save in RAW format.

With that much memory, there's little to be gained with a card, unless you take a lot of photo's without the opportunity to offload to the PC. There is also the autosync with Google to offload anyway, especially if you can do this over wifi.