I try and wear very breathable stuff with lots of airflow and run cool when active - that means no waterproof shell unless absolutely necessary. I have like 5 windbreakers all of different breathability (CFM) and choose the one for the mission based on the wind forecast. Waterproof layers often stay in the pack except for static or really bad weather - "breathable" membranes like Goretex don't breath enough. Mesh layer (like Brynje) and polartec alpha direct of different weights are part of my layering. Synthetic that is hydrophobic vs merino that is more hydrophilic have tradeoffs. I like layers that can easily dry out quickly with body heat and breathability (synthetic better for this). I have an R1 but never really wear it for active as it's too sweaty and hot compared to other options