You might be right. I go back and forth on it, but I am starting to subscribe to the idea that between Lodestar and Laugh Tale, everyone who was on this doublespread and their subordinates will be involved.
Oda wants to dwarf Marineford, i feel like this is the only way he can reasonably do it. Not to mention, a few characters make offhand comments about fighting everyone, namely the Marines and WG.
- Luffy's fleet and the other Supernova are likely gathering soon
- Ryokugyuu has mentioned eventually fighting the RHP
- Akainu wants to fight everyone
- Koby wants to stop Luffy
- Garp is now bait for the Marines on Blackbeard's end
- The 4 Yonko want One Piece (meaning they'll come to a head)
- Dragon and Sabo want destroy the WG
- The Serephim and Mother Flame are with the WG
- Imu wants to sink the world
- And more.
I do question if there are any traditional type arcs after this and not just a 200+ chapter war built up over multiple locations since the world is about to start fighting over land