I think we could get into the situation with Nami and her screaming. Oda could showus what is happening there.
Shaka still has to work on the dome to get it under control again so they can flee all. So, that means he maybe needs protection from the Seraphim, while he is working in the control room. That could mean the group (Luffy/Lucci/Zoro/Kaku) would need to split up, with one duo keeping Shaka safe and the other duo going after Nami. But, this is just speculation.
We could alos have more of Shanks and Kidd.