An exercise. Analyze the corporate product design and create an design based on leaks and plausible rumours. The result is a okia Lumia 1025 'phablet' with a 6 inch screen (1920 x 1152px - 15:9!), ca. 8mm thin and much horse power!
I can't help but think that Nokia might have seen this and "borrowed" some of your ideas for the Lumia 1520. There's the number (1520 is a numerical anagram of 1025), the 6" screen size and the two extra tile columns. Shame they didn't "borrow" the rest, really.