What is the optimal way to do that? Find a knowledgeable barkeep to be your guide. There are many different styles and subgenres of rum aside from light and dark rum. By going to a bar where the bartenders know their stuff, you can have an engaging conversation about that.
The Rum Journey app can help with that. For example, if you are in Puerto Rico, we can hook you up with our friends at "La Casita de Rones" in SanJuan. Let's book an experience with one of the bartenders that will guide you and give you a taste of some of #PuertoRico quality rums.