My first consideration is usually to fit the widest tires possible on a given frame. Sometimes that’s 28mm, sometimes, 30 or 32mm, often times wider. The second consideration is the quality of the tire. A 32mm Rene Herse tire rides far better than a 38mm Gatorskin or the like. Wider isn’t always better. The bikes I ride the most have 700c x 38mm Rene Herse tires.