The fact that we keep our house temperature in the mid-60s means that I need at least three layers even when inside. When I go for a walk I throw a jacket over the ensemble, cover my ears and hands, and I'm good to go.
The key, I've realized, is warmth without weight. It sounds like an advertisement for pricey athleisure wear — in fact, I'm pretty sure it is — but it actually works. I feel warm with three layers on, providing one of them is my base layer. And the "weightlessness" means I'm not stuffed like a sausage into my clothes. Warm and still able to bend my arms — what more could I want?