So you mean Doffy is around Flying six level?
Oh boy, oh boy, oh boy Im not gonna argue but you better have your points ready for when someone want to argue this
Points such as how Franky, Robin and Jimbei would be able to beat Doffy
"X of Y", implies equivalence, not equality. Your Grade 3 logic might not be able to process that. Oda literally recycles plot ploints.
Doffy -> Vergo/Trebol/Pica/Diamante. 4 Card Suits. Vergo, the strongest, gets taken out as main villain arc before DR.
Kaido -> Joker/King/Queen/Jack. 4 Face Cards. Joker, the strongest, gets taken out as main villain arc before Wano.
This was the card theme that he drew up all along. Going from suits -> face cards.