In winter I live in tunics, leggings and flats or dresses/skirts with a nice cardigan/blazer, thick wool tights and boots. Flat boots are great and so comfy.

If you like cargos or fishermans/harem pants, as they're usually a bit looser they look great layered with different textures eg. a more fitted top and coat. Or as Ladylove suggested, a different type of pant with a structured fabric like chinos or heavy cotton, with a more flowing top? If they pants are tailored they should give you some shape but without you feeling uncomfortable/like they're a poor fit (oh boy, do I hear you on the jeans situation). They can be really versatile too, so you can dress up or down.