Considering he's the main protagonist of One Piece, it makes sense that Luffy would gradually grow stronger over the course ...

With Luffy being one of the Four Emperors and having a fleet of 5640 members strong, the fleet is plenty strong on its own, ...

So, there's no doubt that Luffy shone the brightest at Dressrosa. Then Luffy and Law had to split up at Zou as Luffy wanted to get Sanji back, so Law was not involved in the Whole Cake Island arc.

Luffy had ruined the huge wedding cake the size of a house that Big Mom had been looking forward to eating at Sanji’s arranged wedding.

One Piece Episode 1071 shows Luffy’s new Gear 5 power, which complements his personality — as seen with him laughing and his eyes popping out while fighting.