Bit disappointed with our current selection of roofing given that thatch probably was not one of the first choices of scandinavian peoples in building homes. Shingles are cool in concept but their weird spiky design ruins roof edges and makes builds look weird. Tarred shingles would be much better if they were modeled as the standard sort of square shingles that you'll see all over the place in old buildings. In addition to this, sod roofing would be a very good addition given how common it is in viking constructions as well as due to it serving as a good early game alternative to a thatch roof.