Oh boy. I've had exactly two viewfinders die in my life. One was an EVF, one was an LCD.
An electrochromic aperture isn't an aperture, it's an ND filter. You can reduce light that way but you can't stop down to change DOF.
of course you can. it just needs to be engineered to make the translucent portion perfectly round and variable in size.
like here, for example: http://www.patentlyapple.com/patently-apple/2014/06/future-smartphone-cameras-may-use-a-micro-electrochromic-iris-made-from-smart-glass-eliminating-the-use-of-actuators.html
I don't care, HOW they make it. I just want it to be perfectly round, 100% mechanics and vibration-free, small, light and designed for 10 million actuations. :-)