Why spend 20 + g for Unico , you have good ducts, maybe insilate them. I
do not know If unico can reach Seer of regular systems. Perhaps slowing
fan speed or restricting air flow with a filter to remove humidity will
help. You risk freezing the coil , so monitoring temp at the coil would
be #1. Ive heard of a freeze stat on the coil. I have a oversized system
also. I run a dehumidifier and slowed fan speed . But I will put in a VS
DC furnace soon with fan speed controled at my thermostat, and a coil
freeze stat and remote coil thermometer.