But as said above, Oda is average at building it all together. The world feels empty and non-existent without Luffy and the straw hats present
Don’t agree.
Take out Luffy and his crew- which obviously has a detrimental effect on how you examine the series, rare is the series improved by the removal of it’s main characters- and the world building is still very good. The setting of the sea-based, island world, the various factions like the World Gov (which itself has multiple factions), the Yonko, the Balance of Power between them, the RA, independents (people of Skypiea, the Fishmen, the giants), the big mystery of the Void Century, devil fruits and Haki, smaller things like Den Den Mushi, bounties, meito, dials: these are all aspects that combine to create a very well made, interconnected world, even without the Strawhats.
Again, considering the medium it is told in, there is absolutely nothing like One Piece when it comes to worldbuilding.
A lot of it is also just goofy for the sake of it.
A stylistic choice that Oda has been consistent with since the very beginning. Complaining about One Piece being “too goofy” is like saying Berserk is “too gritty.” The series opens with a kid eating a magic fruit and turning into a rubber man, that should be a clear sign that it’s not taking itself seriously, much like Berserk opening with Guts having sex with a woman, who turns into a monster, then gets her head blown off by him is a give away that this is not for kids.