Zoro and Sanji will always be Luffy's wings.
Yamao being able to singlehandedly stall a serious hybrid Kaido makes her stronger than Sanji, ruining the M3 dynamic. We've had strong characters join the crew before, but every time they did Oda always kept them weaker than the M3 when the final fights came. Jinbe and Franky were the most questionable but both times Oda had Zoro and Sanji fight much stronger opponents at the end of arc match ups.
With her strength, Yamao would be better suited as a strong ally. Someone like Marco.
Carrot's power level safely slots in with the crew. Just as Jinbe is between the monster trio and the mid trio, she's between the mid and weakling trio. Overall the crew will remain just as balanced as it was during the Luffy-Brook period.
Luffy/Zoro/Sanji
Jinbe
Franky/Robin/Brook
Carrot
Chopper/Nami/Usopp