insulation, fixed on the outside wall, allows a continuos and low thermal bridge construction. The insulate material is adequate for all insulation requirements.
Heat accumulation resp. heat up is mostly prevented because of ventilation between insulation and facade. The outside wall heats up lightly and slowly. The outside fluctuation of temperature has mostly no influence of the room temperature.
Partial penetrating water will be ousted from the airflow shortly, so the insulation remains in function.
By meaning of building physics the ventilated facade has the most safety function, with diffusion open heat insulation simply ideal. No need of a vapour barrier.
more wallthickness means more heat accumulation capacity of the room-components. In case of short interruption of the heating facilities, or if capacity is reduced, the temperature equalization is made.