Jaco could be the most interesting and the most boring boring bass player in the world in the same song. You can really tell from his live recordings that on some nights, he was pure genius, while on others, anything but. His groove was impeccable when he could keep it together, but the mental illness that made his life a mess also made his playing one, too. His instability may have contributed to his creativity but unlike Jimi on guitar, his closest musical analog, Jaco pioneered a completely new way of looking at the bass, simlutaneously adding melody(ies) harmony and rhythm to an instrument whose most adventurous excusion to that point had been countermelody or rhythm.
Everything Jimi did on guitar had been done before by others separately. He just added it togther, incorporated technology and took it to the next level. I'm not detracting from Jimi, but it's not an understatement of his talent to say that he had the discipline to know when to color between the lines while Jaco simply through the rule book completely out the window. Jimi's social standing required that he have a functional understanding of the world in order to survive to make music. Had Jaco been black, we would have never heard of him because he wouldn't have lived to make the music he did. His premature death is a testament to that.