Ivo-goji wrote:Replace the OD with a MOAB.
Left Vivienne alive.
An actual MOAB isn't really all that close to a nuke despite comparisons, with a yield of something like 11 tons of TNT (so like 0.011 kilotons; Hiroshima was somewhere around 20kt, most US strategic warheads are roughly between 300 and 500 kt, and Castle Bravo was 15,000kt). That being said I can definitely understand criticisms about the portrayal of the Oxygen Destroyer in the film and the desire to replace it with something else (perhaps a more "suitable" replacement would be some sort of bioweapon a la the ANEB or some sort of souped-up nerve agent).
Personally I would have kept the Oxygen Destroyer intact, but I probably would have done more with it. Adding a line during the initial Senate hearings alluding to it's existence ("Over the past five years the military has developed experimental anti-Titan weaponry; now it is up to MONARCH to do it's duty and disclose the location of these Titans so they may be dealt with before they can pose any further danger to public safety" or something like that) would have helped. You could then have Serizawa arguing against their usage not only because he believes the Titans are beneficial to the environment, but because he believes the fallout of such new weapons might poison environments for years to come and even potentially start a new arms race ("if they can kill a Titan, what's to stop them from being used to kill entire countries?").
As I've seen some people criticize MONARCH for not "simply" killing off the Titans in their sleep before the events of the film could happen (the argument goes something like even if they couldn't kill Ghidorah they could have at least destroyed the other Titans and mitigated the effects of his eventual rampage) I would have also added a line in which Serizawa argues against attempts to eliminate the Titans on the grounds that he's not sure if they can be killed by human means, and that trying to destroy them could very well simply wake them up and cause them to go on the very destructive rampages the military was trying to prevent. There was a line in the book to this effect, but it was in buried in a later scene.
Later, after the Oxygen Destroyer detonates in the Gulf of Mexico and seemingly kills Godzilla we get a scene between Serizawa and Stenz on Castle Bravo where it is revealed that (aside from failing to harm Ghidorah) the weapon has worked too well; instead of merely "killing everything in a two-mile radius" it has contaminated a large swath of the Gulf, effectively turning it into a dead sea. Serizawa is furious, telling Stenz that not only have his actions directly resulted in perhaps the largest man-made ecological disaster in history, but by killing Godzilla humanity and all other life on Earth now has no defense against the ravages of Ghidorah and his army of Titans. "Had you simply waited a while, Godzilla would have defeated Ghidorah and we would not be in this situation!" Stenz tries to defend his actions, saying that he was only following orders and claiming that "no one could have known what was going to happen" before Serizawa matter-of-factly reminds him that he had predicted this very outcome during the Senate hearing. Stenz quietly concedes this point to Serizawa, and both men return to their duties before Mothra arrives and everyone learns Godzilla is really alive.
Later during the end credits news montage it is revealed that despite the ability of the Titans to restore devastated ecosystems the Gulf of Mexico remains contaminated by the OD's fallout; as a result the economies of the region are in ruins, with the fishing and tourism industries all but wiped out. Conclude with something teasing an eventual appearance by Destoroyah.
And I also agree that I would have kept Graham alive, Sally Hawkins was definitely underutilized in this film. Graham having to tell her beloved sensei goodbye before his ultimate sacrifice could have been a really emotional moment, and she could succeed Serizawa as the effective "face" of Monarch in the Monsterverse.
Also, I would have fleshed out Jonah a bit more. Go into how his experiences in Bosnia colored his view of humanity; given the time frame in which he served and where he served he was almost certainly a witness to Srebrencia and the numerous other ethnic cleansings and massacres that occured in the Yugoslav Wars. It would definitely be understandable for a man who had witnessed some of the worst warfare and genocides Europe had seen since the end of World War II to develop misanthropic viewpoints.
I'd also retain the murder of Jonah's daughter, Lilly, from the novel as his final tipping point into insanity, but also tie it into his experiences in Bosnia as well. Like, say that one one of his deployments he found an orphaned teenage Bosniak girl and chose to adopt her and raise her as his own daughter. The two grew close, but soon Jonah is once again called away on deployment. While he is away, his adopted daughter is kidnapped and later found murdered. His anguish over his daughter's death and the police's apparent inability to find any answers soon turns to rage when he realizes that the investigation into her murder is intentionally being obstructed by local authorities as part of the Rotherham scandal. Already deeply misanthropic and disillusioned, this final betrayal by the country he had given so much for finally pushes him over the edge into outright terrorism. He now seeks to use the Titans to tear down the corrupt world order and wipe humanity off the face of the Earth so that he and his "chosen few" may form a society free from the problems that so plagued the old human race, "under the watchful eyes of the first gods." I'd also keep the scenes from the novel where he threatens Madison to keep Emma in line intact (at least one viewer I know somehow left feeling that "Madison was never in any real danger from the ecoterrorists").
And like others have suggested, I'd definitely modify some scenes to make Madison having been misled by her mother about the true cost of her plan more credible. Like someone suggested, having the scene where the terrorists seize the Mothra outpost be a more "quiet" takeover, or at least have Jonah wait until Madison is out of earshot to execute the captured MONARCH scientists. Little things like that, so it's more apparent that Emma misled Madison about the true cost of her plan to free the Titans, or that Madison was only ever reluctantly going along with her mother's plan and the realization that so many people are going to die turns her completely against it.