When writing anthropomorphic fiction, one of the major elements is determining the species and the variety of your cast members. One of your first decisions is should they all be of the same race. While it may be to your fancy to have an entire cast of foxes, the positive side to this is that you can delve into the variations of the species. You can discuss the habits of different types of foxes such as fennecs versus the red fox, as well as highlight cultural differences much in the way that science fiction does with aliens and racial situations. An example would be a story where fennec foxes are considered exotic and used for slave labor, or a case where arctic foxes are racially profiled and perhaps have a unique ability the others do not, such as the creation and manipulation of ice. This also comes with a downside for people that don’t like how foxes tend to be overused within the fandom. They could be turned off by the fact that your characters are all variants of the same species. Additionally, one should consider that in a situation where the entire cast ‘looks the same’ from a general perspective, individual characters may have a harder time standing out.
Another possibility is centaurs or any characters with a humanoid torso and animal lower half. The positive side to this addition is that you can more or less make up your own rules as to the species and what they are like. For one, they are capable of more physical action than most normal anthropomorphic characters, though most of the issues with centaurian species are logistical. If you include centaurs, then cars, furniture, group travel, everything must be modified for the existence of centaurs. Adding an extra two feet to some of your characters can slow you down if you do not have a plan in mind for your four-footed cast members.
Let’s not forget about humans themselves. The plus side to the involvement of humans in furry stories is that non-furries may enjoy the story simply for its own merits. Humans are easiest for people outside of the fandom to understand, and logically so. If you want your story to be more broadly accepted, consider a partly human cast. Be wary of using the humans only on the side of evil though, as the ‘evil humans versus good anthropomorphic characters’ plot line is a frequent staple in furry fiction. It may be seen as ‘one of those stories’ in the same way that comas on soap operas are often not taken seriously.
Finally, a species-diverse cast is yet another option. If you have every cast member a different species, or at least no more than two of any one type, you maximize the chances that every reader will find at least one species they enjoy. Additionally, it gives you more variety in descriptions. For example, if there is only one bovine character in your story, they will be easily recalled and will more quickly establish themselves in the reader’s mind. The pitfall with this approach is that you may have more characters than you can handle, if you attempt to fit too many species into your zoological odyssey.
As a writer, you clearly have many choices for how to populate your world. The choice is of course, up to you. However, bear in mind that you must know what kind of story you want to tell before you begin the casting process. Being aware of this will often do most of the work for you. Think of the characteristics each type of anthropomorphic being will add to your story and then decide if they’re the right one for you. If you’ve done your planning properly, it should seem as if most of the decisions have been made all by themselves.