Do pets that have deviant colors/patterns possess a greater chance of producing deviant babies? I know it's a small chance to begin with, but would breeding a deviant pet with a homozygous pet increase that percentage at all?

No, deviant pets do not increase the chance of deviance. When a pet is born homozygous for a color or pattern there is a 1/10 chance it will be a deviant no matter who the parents are. Deviant pets are only required for the breeding of double deviants.

Okay I see, thanks for the answer and info :)