I was asking myself the above question, so I sat down and came up with a design for a funky QWERTY Lumia based on the design of the Asha 210. Note that the hardware call answer/reject and navigational buttons below the 210’s display are gone, as Windows does not require those. I like this “concept” phone. But chances are that it will never see the light of day.
Perhaps some other manufacturer – maybe a Windows OEM – will dare attempt slapping a QWERTY keyboard on a Windows smartphone. Just perhaps.