Here's a set of questions you should ask yourself when designing your characters:
- Could you distinguish your character from others by just seeing their eyes, nose and mouth?
- If your character fell into a bucket of paint (all original color and patterns lost) would it still be distinguishable from other characters?
- Would you be able to recognize a silhouette of your character from the side?
If your answer is "no" to any of these questions, consider making some changes to your characters. Here are some tips:
- Don't make the eyes the same on all your characters. There's such a variety of shapes you could be using. The size of the eyes, separation between them and distance from the nose changes the character a lot.
- Furries have a very wide variety of muzzle shapes. Some are long and thin, some are thick, some are short, they can be more triangular or more rectangular. The profile of the muzzle from the side is a very distinguishing feature of a character.
- If you're using a template then your character is indistinguishable from any other character made with the same template. This really goes for most Sonic fan characters.
- The mouth can change a lot as well. How far up or down on the face it is and how long it is makes a big difference.
- Fur patterns, like clothes, are not particularly distinguishing features, they are just added embellishment. If by removing the fur pattern your character is no longer recognizable then you need to add some more morphological distinctions.