@Monquito:
The WG would need time to prepare against Dragon, just like they needed time to prepare for Newgate.
First off, we don't know Sabo's status. He may have escaped. I don't expect a new Ace happening, and, if it happened, he would be moved to New Marineford, not Mary Geoise.
What I'm expecting is Hancock's capture and she being brought to Mary Geoise after her secret is ousted.
The government has no idea that Hancock is important to Luffy. Even if Koby somehow finds out, I see him more willing to keep the info to himself.
So, Luffy goes for Hancock, and Sabo/Vivi may still involved somehow, but not in an Ace-like manner in which a trap is set to capture whoever comes for them.
And two big arcs in a row isn't usual either.
I don't think Mary Geoise will be a big arc. I'm actually expecting a short one (akin to Punk Hazard), that leads to a bigger one (Vegapunk).
The Straw Hats get in and out. In the process they find info that is important, meet Bonney and the Revolutionaries, fight Cipher Poll Aegis, cause ruckus by releasing slaves, and escape before the full mighty of the WG assembles.
Then the info they get set them on to Vegapunk's lab to save Kuma or whatever.
Shanks would take whatever task Luffy would wanted to, and go and die(as it expected anyways), right after Shanks death, and Sabo's squeduled execution, Hancock slavery resumed and whatever trouble Vivi is in, it'll be about enough time for Luffy to complete the journey, and with Robin revealing the whole mess of a world the CD's made during the Void Century, Luffy would finally have all the good reasoning to invade Mariejoa, and make perfect narrative sense, unlike what you're proposing right there..
Luffy would never let down a friend under those circunstances just to fulfill his ambitions. That's just not who Luffy is. He doesn't need to learn the ancient history to have a reason to go to Mary Geoise, he already has his friends in need.
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@flandrian15:
I always understood bounties as the threat level someone poses to the World Government or the marines or both. Since we don't know all the reasons the WG gives bounties we can therefor not conclude anything from the amount of a bounty. not strengthwize, not plotwize, not whether someone's a friend or an enemy, …
In the narrative they mean nothing. Therefor their hype is misplaced.
The level of threat carries a level of power that the person has to resist the government's attacks.
While not every high bounty means high power, there's a correlation more often than not.
And hype is hype. It's very real. People got hyped with Jack's bounty. They got hyped with Katakuri's bounty. It's through bounties we know characters like Smoothie are strong despite never seeing her do anything. You may not like that it creates hype, but that doesn't change the fact that it does.