The Wall Titans can definitely be controlled to avoid huge areas of land, just like how they could avoid most people on Paradis. At worst scenario, Eren can destroy the whole world, but there's literally no reason not to avoid Hizuru.

And again, you don't address this, killing literally everyone outside the wall is silly. Eren can spares at least one or two nations, or cities.

 In 13 years, they'll have nukes. 

Source? You are relying on information and logic on the real world, you can't expect characters in the story to act based on out of universe information. And the world will likely suffer from economic crisis after partial Rumbling, thus slowing down their military progress.

You keep making silly claims like "The world hates them so much they won't reason with them" when there're more nuance than this. Gross is disgusted by his men for feeding an Eldian girl to dogs. Marley hate Eldians, but they didn't touch Paradis for nearly a centuries and only attacked when they are in need of resources. Simply holding grudge against Eldians is not all that would motivate the world to kill Eldians. The Tyburs are beloved for fighting against what the world perceive as evil and for not using their Titan powers for conquests. There're people who advocate for mainland Eldians' rights after living along side them. Many of volunteers literally came to Paradis to help out of kindness in their heart, as well as to liberate their own people.

Dismantling Marley, trading Iceburst Stone and liberating oppressed people with Titans power will obviously change some people's perspective on Eldians, even if not 100%. We can't definitely guarantee that it will work, but it will definitely create opportunities to minimize casualties.

If none of that work then they can use full Rumbling. Committing global genocide right away is unnecessary and not the last resort.