whiskers are probably drawn onto naruto for artistic effect and as a constant metaphoric reminder for the audience. also, judging from the impression from the kids from konoha, they never notice naruto's whiskers. this is weird considering how naruto is the only person seen in the anime that has whiskers. we've seen naruto being referred to as a brat, but never the weird kid with whiskers.

about naruto healing so quickly, there's the concept of chakra in the naruto world. he heals by drawing the chakra from kyubi. during the chuunin exam, neji noticed the differnet chakra that was being drawn out from naruto's belly, which healed naruto quickly. if he already had the genes, then there would be no point for him to "call upon" kyubi's power.