I hadn't read the history until recently. Now that I have more thoughts.
There can be a lot of discovery and establishing. What I mean is the warlords, yonko, and Impel down didn't always. They were created because of the pirates being an increased problem.
Impel Down Something like that could take so long to build so it would probably be better have a grand opening, press release distributed. Marines/WG are going around transferring the worse prisoners from affiliated islands. This also gives non affiliates motive join.
Yonko/Warlords Currently the show has the Worst Generation. Maybe we name the generation and or Age (Bronze, Iron,__). Out of the pirate problem the warlord system is born. I wouldn't let more than 2 players have this initially unless there is site explosion and there are many viable candidates. Stock with strong npcs
Then later on an event maybe just before the NW where a pirate(s) in the NW are named emperors.
There should be short news clips of Npc pirates actions that will have real impact on the world. That way when they get their positions warlord/yonko it isn't the first time they are heard of
Some islands could also just now be building or discovered. FYI
JAYA HASN'T SPLIT APART YET.
Ohara is still intact
Maybe make it so the big book of DFs isn't written yet. Therefore most people in the world don't know about it. There its magic a curse blessing w.e.
