Is a PTHP an HVAC option for a super or well insulated structure?
The point of a super insulated home or a Passive house is that they rely on the body heat of the occupants plus the heat from the various gadgets in the home to keep them warm, with the insulation slowing the heat loss.
A home built to Passive house standard will usually be fitted with hydronic heating (probably as the new owners are not sure that it will do what it says on the tin.) And the heating may never be used.
Of the 37, 000 Passive houses in the world, 20, 000 or so are in Germany where 92% of the owners are satisfied with their economy. 
A true Passive house is almost air tight, with a heat recovery ventilation system, fitted with a in duct heating coil to warm the incoming cold winter air, should it be 3.5C or more lower than the room temperature.
You can see from the above that having a large hole in a wall, albeit sealed with a steel sheet, where a vast amount of heat can escape will defeat the whole point of carefully installed insulation.