If your commute is mostly on the roads, then consider a bike with 700cc wheels with narrower winter tires,.. IME they roll better and are easier to ride through "traffic snow and slush", then a 26' wheels with wider tires. Narrower tires cut through, while wider tires just slide all over the place. Wider tires are only better if you're riding off road on frozen rutted hard pack snow along MUPS and off road trails.