Honestly, I don't think it'd be anything deep. Just whatever is labeled as preset one for human female Tav. And if there is any reason, it'd likely to create variety between presets as you flip through races like Half Elf, Elf, Halfling, Human. Differences can make them stand out and make it easier for someone to figure out what type of character they want to play. Tbh, I am not sure why this would really be something anyone would notice, especially since the Male Human is Default Tav in a lot of people's eyes (even though when I start the game up Female Elf is always the default so that must be true Tav, Tav Prime, the Tav to merge all Tavs.)