1. Chelsea Wolfe: Wolfe's music incorporates elements of gothic rock, doom metal, and folk music. Her vocals are haunting and powerful, providing a stark contrast to the heavy instrumentals.

2. Oceans of Slumber: This band's music is a blend of progressive metal and doom metal, similar to Tool. The band's lead vocalist, Cammie Gilbert, has a powerful and soulful voice.

3. In This Moment: A metalcore band fronted by Maria Brink. Their sound is heavy, but with a theatrical edge. Brink's vocals range from clean singing to harsh screams.

4. Jinjer: A Ukrainian band known for their mix of progressive metalcore and groove metal. Tatiana Shmailyuk, the lead vocalist, stands out for her ability to switch between clean vocals and harsh growls seamlessly.

5. Kylesa: Sludge metal with psychedelic rock, much like how Primus blends different genres. Laura Pleasants has provided vocals for many of their tracks and has a distinct voice.

6. Halestorm: Classic hard rock sound and the powerful vocals of lead singer Lzzy Hale.

7. Madder Mortem: Progressive metal with experimental and avant-garde elements. Their vocalist, Agnete M. Kirkevaag, has a distinct and versatile voice.

8. Sleepytime Gorilla Museum: Avant-garde music with progressive metal and experimental rock, which might appeal to a fan of Primus.