Very good chapter. Really enjoyed that one.
Things finally seem to move again. We've seen a glimpse of roughly all major fights around Onigashima except Killer/Hawkins and Drake/Apoo, then everyone was made aware of Luffy's defeat plus Kaido coming to finish what's left. If Onigashima was already roughly above the capital it would've been perfect to me.
The small heavy hints that Oda threw in there are also very significant as most pointed out.
Wano being a turtle does make sense because
1. Momo hear something.
2. It will fit the 4 Chinese Gods Mythology. (Azure Dragon, Byakko, Suzaku, and Genbu)
So I guess this theory becomes true after all.
Yamato is for sure the white Tiger while Marco probably symbolizes the remaining one.