Comfortable touring handlebars are often a function of hand positions. Usually, the more the better. Additionally, some people are prone to hand pain issues and certain types of positions may look comfortable but stress the hand in such a way that pain issues, not easily alleviated can be a problem. Make sure you have a good idea of how your current hand positions may translate on bars with different geometries and shapes.
Function is about what goes where on your handlebars. Some have borrowed the term “cockpit” management. Everything in it’s place, easy to find if you’re not looking and easy to see when it’s necessary. Touring handlebars come in many varieties. Positioning brakes/shifters, lights, computers, GPS, phones, and other accessories, if you have them will need some thought and analysis.