I picked up an ASOS 3/4 sleeve scoop-neck, sized up one to large. I'm glad I sized up; I'm pretty sure a medium would be too small in the shoulders, and an open-necked shirt with narrow shoulders makes it look like you stole your GFs shirt, IMO. It's a little shorter and a hair boxier than it ideally would be. I'm gonna give it a cold wash and try to stretch the body lengthwise a little before I wear it.
Also, it's cold enough here that I'm still wearing v-neck + henley + flannel + cardigan or jacket every day.