Marley needs to be destroyed. They're too evil, and it seems the majority of the government and civilians are complicit. Paradis needs to just chill the fuck out, which if they destroy Marley, they'll be able to. The rest of the world won't want to fuck with them after they see that even with anti-Titan guns, the Titans can still win. The whole world is trying to crush Paradis to take their resources, so I have a really hard time thinking of our Wall Eldians as bad guys, regardless of what they do. In war, when your everything is about to be devoured, do whatever it takes to survive.