You're not off base.
The "Total Control" tests the pH and ORP and adds an acid solution when needed, and generates chlorine when needed. Salt systems do not affect the Cyanuric Acid, Total Alkalinity or Calcium Hardness levels like bleach or tabs do, so there is very little need to constantly monitor and adjust these parameters.
Sure you can do this manually, but then again, you can add chlorine manually too.
Currently there are no electronic methods to test and control alkalinity, calcium or cyanuric acid, commercially or residentially, so your quest for your total control system is not yet available... but....hmmmmm.....