Tbh, i think this is where you and me might differ on stuff.
I've always had the mindset that Shanks is the emotional close to this series. Whether Luffy dies, whether he returns the hat, etc. One of the last major interactions you'll see is Luffy and Shanks. I personally believe this because the ending has been planned from the beginning, and Shanks is one of the few notable Chapter 1 characters.
I've very much have been on idea that even after Marines, Blackbeard or the WG, this story will always come back to Luffy and Shanks. It's basically what it was always built off of.