None of the arguments against this are valid. a) speed it up by putting a shock collar on the ump and when he screams in pain, it's a strike (or, I guess, just put a speaker there that yells "strike" or "ball" in Samuel L. Jackson's voice or something) adjust the rule if you want the zone to be smaller, or more consistent. Instead of "from the midpoint between the cock and the chin to the kneepit" change it to "from 35CM above the ground to 90CM above the ground" or whatever you decide.
It's not going to be seamless, but it's forfteenbajillion times better for everyone involved once they get used to it.