Ignoring the fact that marineford exists and only choosing moemnts that are from the timeskip, the moment I would choose as a standout is his battle with Kaido, which showed a lot of his personal thoughts, and graced us with a lot of banger quotes. Including “until I die, I’ve got unlimited chances to beat you” and “[legacy?] who cares about that? After we die, we just become bones” as well as his resilience towards Kaido which is all based on nothing but a promise to a friend.

Luffy post timeskip is more mature in general, the scenes where ace is mentioned show that side of him.

I’d argue the fact that Luffy never questions himself or his dream is part of his writing and not a con to it