Idea: heat and cool the seats and dashboard directly. I estimate 50 watts thermal per passenger,(max). Average passenger cooling watts probably closer to 35 watts thermal, even on 120F Phoenix days.
Cool the dashboard to a thermostatically regulated temp of 95F.
I would suggest a water chiller such as used for chilling down fish tanks, but obviously adapted for DC input power and compactly packaged.
Cloth steering wheel so I don't have to grab a scorching hot piece of leather in the Phoenix hell heat.
On heating side: 50 watt resistive heaters per seat. Resistive heating element in the steering wheel. Resistive heating element (or electronics waste heat pumped?) for the dashboard & window defogger vents.
I am convinced that Aptera has both the engineering talent and tools (simulation etc.) to analyze some number of alternatives and select the most efficient (Remember that is their underlying goal) for all Aptera system within available near term potential solutions for inclusion in a prototype ready for qualification and testing for production late this year or early next year. I do not believe that we, as lay observers have the tools to sufficiently analyze solutions for the production version. These could ideas can be the basis for determining the next upgraded version once Aptera is successful and has a strong capitalization