If I could rewrite the fights in Onigashima, here’s what I’d do:
1. Chopper vs Page One: Oda teased that Usopp would fight P1, but then he shafted Usopp and had BM one shot P1 for no reason. I would have preferred that Usopp beat P1 over what happened in the manga, but I think Chopper vs P1 would have been even better since they’re both brute force fighters. Chopper also should awaken CoA during the fight
2. Nami vs Ulti: Just make the right better. Give at least one full chapter of Nami vs Ulti after Nami gets Zeus back. Also maybe have Nami unlock CoO during the fight
3. Franky vs Sasaki: Keep it mostly the same, but make Franky unlock CoA during the fight
4. Robin vs Black Maria: Keep mostly the same, but make Robin unlock CoA during the fight
5. Brook vs Who’s Who: Oda can still give us a little bit of Jinbe vs WsW, but have Jinbe jump into the ocean to rescue Luffy, leaving WsW unattended. Have Brook unlock CoO during the battle.
6. Inu vs Jack: Have Jack pull out Awakening in order to barely get the W over Inu. Inu still gets to do his attack where he impales Jack in the stomach, but Jack survives it because of his Awakening and good endurance. This wound will come into play later though.
7. Neko vs Perospero: Have Perospero create a candy dome around him and Neko. This would block out the moon, causing Neko to be forced out of Sulong. Perospero then beats Neko due to Neko being weakened
8. Carrot vs Perospero: Carrot saves Neko and finishes off the weakened Perospero
9. Usopp vs Jack: With Jack having beaten Inu, the mid trio, Chopper, and Nami being exhausted from their fights, Luffy and Jinbe out of Onigashima, Yamato being busy with Kaido, Kid and Law being busy with BM, Killer being busy with Hawkins, and Drake being busy with Apoo, no one is left to stop the All-Star Jack from ravaging through the samurai army. Usopp would start off this battle from a range, taking advantage of the fact that Jack has to be in CQC to do anything. Usopp would be bombarding Jack with ranged attacks, which would obviously be doing barely any damage, but would still be adding up over time to the already weakened Jack. Usopp would also be laying traps as Jack tries to approach him. During this segment of the battle, Usopp would be using his CoO to sense where Jack is going and stay one step ahead of him. However, it wouldn’t be enough. Jack would eventually catch up to Usopp. In one last desperate attempt, Usopp would try to use his ultimate attack against Jack (whatever it is) and aim for Jack’s weak spot, which is the area where Inu had stabbed Jack (since hitting someone hard where a serious wound is causes a lot of pain). In the process, Usopp would awaken CoA, giving his attack just enough extra strength to KO the already very tired Jack. Of course, Oda could make Jack as weakened as he needs to be for Usopp’s victory to be believable. Having defeated Jack (with a lot of help from Inu obviously), Oda would get to maintain Usopp’s gag of getting a much higher bounty than he deserves since he would be given credit for Jack’s defeat.
10. Jinbe vs Smoothie: After saving Luffy from drowning and bringing him to the shoreline, where the Heart Pirates and Kid Pirates will also be at, the Chanter finally makes it over the waterfall and arrives at the location where Luffy and Jinbe are at. Luffy is still unconscious, so Jinbe and the others must protect him from the BMPs. Jinbe has an epic water battle with Smoothie.
11. Heart Pirates and Kid Pirates vs other BMPs: Bepo takes on Snack (assuming that the anime is right about him being there), Heat and Wire take on Compote and Daifuku, and the others take on the various other ministers present on the Chanter. Once Luffy recovers, he has Adult Momo fly him back up to Onigashima, like in the manga.
12. Sanji vs Queen: Same as in the manga
13. Zoro vs King: Same as in the manga
14. Killer vs Hawkins: Same as in the manga
15. Drake and Apoo vs CP0: Let Drake beat Maha so that he actually gets a W, instead of having Izo beat Maha. Let Apoo beat Sunflower Mask Guy. Meanwhile, Mr. Go will be assassinating WsW, since it was mentioned earlier that they want WsW to die. He shows up after his men are beaten and KOs Drake while Apoo runs away.
16. The Scabbards: As mentioned earlier, I already had Inu and Neko losing their fights. I would honestly just remove Kiku and Kawamatsu from the story since they accomplished literally nothing. Raizo vs Fuku still happens. Kinemon vs Kanjuro still happens, but is an actual fight this time. Denjiro hunts down Orochi. Ashura Doji still sacrifices himself to save the other Scabbards.
17. Law and Kid vs Big Mom: Same as in the manga, but have these two also learn some form of advanced Haki during the arc so that their victory feels less forced. Maybe Law gets AdvCoO, which makes it easier to land hits with his hax DF, and Kid gets Adv CoA, which makes his attacks more powerful
18. Luffy vs Kaido: Same as in the manga
1. Chopper vs Page One: Oda teased that Usopp would fight P1, but then he shafted Usopp and had BM one shot P1 for no reason. I would have preferred that Usopp beat P1 over what happened in the manga, but I think Chopper vs P1 would have been even better since they’re both brute force fighters. Chopper also should awaken CoA during the fight
2. Nami vs Ulti: Just make the right better. Give at least one full chapter of Nami vs Ulti after Nami gets Zeus back. Also maybe have Nami unlock CoO during the fight
3. Franky vs Sasaki: Keep it mostly the same, but make Franky unlock CoA during the fight
4. Robin vs Black Maria: Keep mostly the same, but make Robin unlock CoA during the fight
5. Brook vs Who’s Who: Oda can still give us a little bit of Jinbe vs WsW, but have Jinbe jump into the ocean to rescue Luffy, leaving WsW unattended. Have Brook unlock CoO during the battle.
6. Inu vs Jack: Have Jack pull out Awakening in order to barely get the W over Inu. Inu still gets to do his attack where he impales Jack in the stomach, but Jack survives it because of his Awakening and good endurance. This wound will come into play later though.
7. Neko vs Perospero: Have Perospero create a candy dome around him and Neko. This would block out the moon, causing Neko to be forced out of Sulong. Perospero then beats Neko due to Neko being weakened
8. Carrot vs Perospero: Carrot saves Neko and finishes off the weakened Perospero
9. Usopp vs Jack: With Jack having beaten Inu, the mid trio, Chopper, and Nami being exhausted from their fights, Luffy and Jinbe out of Onigashima, Yamato being busy with Kaido, Kid and Law being busy with BM, Killer being busy with Hawkins, and Drake being busy with Apoo, no one is left to stop the All-Star Jack from ravaging through the samurai army. Usopp would start off this battle from a range, taking advantage of the fact that Jack has to be in CQC to do anything. Usopp would be bombarding Jack with ranged attacks, which would obviously be doing barely any damage, but would still be adding up over time to the already weakened Jack. Usopp would also be laying traps as Jack tries to approach him. During this segment of the battle, Usopp would be using his CoO to sense where Jack is going and stay one step ahead of him. However, it wouldn’t be enough. Jack would eventually catch up to Usopp. In one last desperate attempt, Usopp would try to use his ultimate attack against Jack (whatever it is) and aim for Jack’s weak spot, which is the area where Inu had stabbed Jack (since hitting someone hard where a serious wound is causes a lot of pain). In the process, Usopp would awaken CoA, giving his attack just enough extra strength to KO the already very tired Jack. Of course, Oda could make Jack as weakened as he needs to be for Usopp’s victory to be believable. Having defeated Jack (with a lot of help from Inu obviously), Oda would get to maintain Usopp’s gag of getting a much higher bounty than he deserves since he would be given credit for Jack’s defeat.
10. Jinbe vs Smoothie: After saving Luffy from drowning and bringing him to the shoreline, where the Heart Pirates and Kid Pirates will also be at, the Chanter finally makes it over the waterfall and arrives at the location where Luffy and Jinbe are at. Luffy is still unconscious, so Jinbe and the others must protect him from the BMPs. Jinbe has an epic water battle with Smoothie.
11. Heart Pirates and Kid Pirates vs other BMPs: Bepo takes on Snack (assuming that the anime is right about him being there), Heat and Wire take on Compote and Daifuku, and the others take on the various other ministers present on the Chanter. Once Luffy recovers, he has Adult Momo fly him back up to Onigashima, like in the manga.
12. Sanji vs Queen: Same as in the manga
13. Zoro vs King: Same as in the manga
14. Killer vs Hawkins: Same as in the manga
15. Drake and Apoo vs CP0: Let Drake beat Maha so that he actually gets a W, instead of having Izo beat Maha. Let Apoo beat Sunflower Mask Guy. Meanwhile, Mr. Go will be assassinating WsW, since it was mentioned earlier that they want WsW to die. He shows up after his men are beaten and KOs Drake while Apoo runs away.
16. The Scabbards: As mentioned earlier, I already had Inu and Neko losing their fights. I would honestly just remove Kiku and Kawamatsu from the story since they accomplished literally nothing. Raizo vs Fuku still happens. Kinemon vs Kanjuro still happens, but is an actual fight this time. Denjiro hunts down Orochi. Ashura Doji still sacrifices himself to save the other Scabbards.
17. Law and Kid vs Big Mom: Same as in the manga, but have these two also learn some form of advanced Haki during the arc so that their victory feels less forced. Maybe Law gets AdvCoO, which makes it easier to land hits with his hax DF, and Kid gets Adv CoA, which makes his attacks more powerful
18. Luffy vs Kaido: Same as in the manga