Touch screens on pro level bodies? It's probably inevitable but just so long as they are there as an option. Properly located buttons & joysticks that fall naturally to hand without taking your eyes off the action are a must...at least until instant, perfect voice control takes the stage.
And that would want to be a whole lot better than Siri. Can you imagine it? "Siri, focus on the eyes...no, not those eyes, the other ones...hey that's a nose...oh forget it...Siri, switch to full manual...no not the user-guide manual...SIRI behave !!!! (coming this century)
There's a place for touch-screen for something like Q or Info, but please, not for the menus. And no Siri.