That's a rough call because of each having a go at carrying the tribe. In the Primal years, they were a wonderful team that filled the space like nobody else. The rattles, shakers, cow bells, and other percussion instruments were smartly, sparsely used to bring Dark Star and the spacier places into further depths. The subtle dynamics were extraordinary. Then Bill driving the band like an overbuilt locomotive when he was all alone. But when Mickey returned, Bill went on vacation and really never established dominance again. Mickey became the primary energy between the two. He came back with ideas and a vengeance. Mickey was relatively consistent with strong energy throughout the 80s and 90s, whereas Bill showed up here and there and played in a similar inconsistent manner as Jerry. He was going through the motions for a long time there, and Mickey picked up the slack.
I don't have a favorite between them, and I don't have a favorite period because of either of them. My favorite periods involve some things they offered, but I would never say I was sorry to see Mickey go or for him to return. I know a lot of people like '71-'74 so much that they weren't excited to see Mickey's return. I'm sorry the dynamic changed like it did, but I'm not sorry Mickey came back. I missed him, though Bill was incredible by his lonesome.
You aren't interesting or clever when you write or speak in the lyrics of others. Rather, what are YOUR words?