Funny enough, the whole Journey vs. Serialization thing make sense if you put into context Roger's journey.
- Roger found One Piece/Laugh Tale/True History.
- Roger was too early to do anything about it.
- Rayleigh says the exact same thing like 450 chapters prior
This very likely means that Luffy must find One Piece, learn everything, THEN do something about it that Roger couldn't do because he was "too early".
Yeah, this going to be my structure the remaining series. 5 years until Luffy's journey ends, but an undefined amount of continued serialization until the actual, physical end of the manga (Final War when Luffy can actually do what Roger couldn't).