The important thing about Bathory was that they did something new. Without Bathory, there would have been no Darkthrone, and without Darkthrone, there would have been no black metal as we know it today. Even if Bathory's music was minimalistic, which it is not, compared to many other black metal bands, it is the innovative quality that counts. Complexity does not = good music. Take Dream Theater for instance, they are complex, but are one of the WORST bands ever passed off as metal. Bathory, Possessed, Tormentor, Death, were great bands developing the genre of metal.