I, and many others, would definitely disagree that the intellichem is overkill
As far as your comments on the ORP sensor, I have personally observed a couple pools running on liquid chlorine, where the intellichem works perfectly with a CYA level of 30-50. The only case where the intellichem is not ideal for ORP control, is with a salt cell, due to high TDS and CYA
The intellichem is rock solid for PH control - perhaps my favorite piece of equipment. My ph is steady at 7.5 all the time and I've never had to recalibrate the probe. Since I purchased my unit with the rest of my pool equipment, I have a 3 year warranty, which is also reassuring.