To me a good concept is one that follow all the leaks and look authentic that try to predict how the next device will look like, in other words: increase the thickness to 9mm, make the top and bottom bezels even in size, move the camera to a bit above the center of the back (it is pretty much impossible to place a huge camera sensor like z2's on top with ultra thin top bezel), replace the xenon flash with dual LED, update the sides with the leaked right and left metal frame, remove the docking port cause according to the frames sony is going for waterproofed usb port and wireless charging so also make the usb port exposed, just look at the leaked frames. the base is a good start but try to make it look authentic and not like cut and paste and not wishful thinking spec.
if you do what i wrote your concept will look a lot better.
I think only camera part is where i added too much unrealistic specs
About image i am very poor at editing stuff.
It took me hours to make them image and you can still find many errors in it
Edit: Made some changes in camera specs as well as attached a more refined pic with led flash and waterproofed usb port btw the sides are pvc coated in black the leaked frame seems white version
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