The electronic thermostat will not deliver colder air temperatures.
What it will do, is more accurately control the compressor, thereby alleviating the freezing up of the evaporator coil.
To increase interior cooling, the best thing to do is insulate.
The point of my OP was to try to determine what air temps it will deliver.
Actually, i think that while insulation is useful, increasing the airflow is key. Using the old style thermostat I have no issues with icing. I was playing with an adjustable style, but it is not located properly and did allow icing.
I am also wondering if the TXV is not properly spec'ed, but that is way above my pay grade