As of right now, would Chisa be an upgrade over SK for a Zaphi team or solo Cartwheel?

I'm currently running my Zaphi team with S0R1 Zani, S0R1 Phoebe, and S1R1 Shorekeeper, while my Cartethyia only has Aerover and SK. So I'm wondering whether Chisa could improve my Zaphi team at all, and whether there is any point in getting Chisa for Cartwheel when I don't have Ciaccona.