Doesnt matter how progressive he is. He is still the one who is in charge of the rape and forced enslavement of several thousands of elves and he will always be a piece of shit. Its like saying Hitler was a nice person because he loved animals - while it is true that Hitler was kind to animals you cannot ignore the fact that he still killed millions and was a horrible person.
Cornwall is the same. You cannot say he is a nice person simply because he gave elves a few rights when he is either directly or indirectly responsible for so many atrocities committed against them. Simply ignoring all the shit acts he is responsible for just because he gave them a few basic rights when he is still completely fine with rape, enslavement, treating them like animals etc is a bit dumb in my opinion. And even if he changes in the future it does not change the fact that he still committed those crimes. If a mass murderer in real life says he is sorry it does not erase his past crimes does it? The murderer still gets his sentence. Similarly even if Cornwall changes I still think he should be held accountable for his actions because simply changing does not erase his crimes or the suffering he was responsible for.
That said you have a story to tell so just develop the game however you want. You have been doing a good job so far and if people do not like it then it cannot be helped. My opinion is that you should not try to paint Cornwall as some kind of hero because he is not - he is a piece of shit. But if you think differently and if you want to portray him as a good guy then thats fine too and I can live with it. One does not need to agree with every single decision the author makes to enjoy the end product.
Uh, well, I think you may be missing a lot of the story. 300 years ago, the new world was found by Crusaders, they then found Elves (Who attacked them) and called them demons. Once that crusade ended, all Elves became slaves. A person and or people were appointed leaders to control the Elves. The first person, who was likely one of the Crusaders, decided all Elves are nothing but animals, and deserve to be put to work.
Then governments started advertising this new land. "Free land! Cheap labor! Colonize now, and you'll be rich!". Everybody who moved there was ecstatic to learn they could become rich, and live a good life. All they had to do was move. "Elves? Wait, so you're saying I can hire an Elf? Hold on, I don't need to pay them? My family can just live the good life and all I have to do is move?"
So it began, people moved, people bought slaves, peoples standards of living went up. Nobody died of hunger, even the Elves. But of course, they had no rights. It was down to a person's own morals how they treated their Elves. There wasn't exactly a "Oh! Let's rape em all!" mentality. If people wanted free labor, they treated them nicely, or broke them. Both were very real cases.
Once that leader, we'll call him the Elf Ambassador, died or no longer wanted the job, someone else would be appointed. Based on their views of the Elves, he or she could implement laws, give them rights, or take them away. Nobody was certain what to do with Elves, but that's how the history went down. "What's the point in changing something that has worked perfectly?" People thought.
So nothing changed. Elves stayed slaves, some laws went in and out of fashion for Elves.
Fast forward to today, Cornwall is the Elf Ambassador. Except this time, he surrounds himself with friends, friends with different opinions. One of them is a collector of rare Elves, he likes to make profit off of selling Elves. One of them likes treating his Elves as his pets, one of them likes that he can do whatever he wants to them. However! Cornwall will not allow the rape of Elves, even though he sees them as subhuman tools, he believes they conscious, he believes they have feelings. He doesn't want to hurt the Elves. So he takes away every Elf that man has owned, and locks him up in jail. As you already know, Autumn's father is one of his friends. Cornwall chose him due to his pro Elven politics, just to have another opinion.
For the first time in Human history, Elves now have rights. They're treated with care now. Elves are actually given to poor families for extra work around the house. Cornwall's move. Elves now help in classrooms with young children, preparing food, fetching supplies, or helping a teacher to prepare work, and even giving children extra attention. Cornwall's move. There is now something called the Happy Home Initiative, or HHI, which allows an Elf to choose whomever they want to live with. This results in that person having a 10% discount on that Elf. Cornwall's move.
Hitler was regressive, and Cornwall is progressive. He's not the best guy, but in the first time in Human History, Elves aren't treated like trash, now they're treated like tools. Which is a huge step forward considering nobody cared if you worked your Elf to death, nobody wanted them near children, everybody thought of them as disgusting demons who deserved to die. Culture is now shifting, and this is all because of Cornwall. Granted, it also wouldn't happen without Autumn's father, but they are both equally responsible for the good to come this new shift, others would have ignored Autumn's father, while Cornwall listened.
I'm not saying Cornwall is the best of people, but he is the best thing to happen to Elves, ever. (I'm not saying everybody should thank Cornwall, I'm just saying if Humans and Elves were equal, Elves would be living a life 100x better than before Human's showed up. Even at this very moment in history, an Elf's quality of life has improved just a little since before Humans showed up.) Nobody will ever allow Autumn's father to be the Elf Ambassador, his views are insanely radical to everyone on the continent. Are his views the right way to go? To us, absolutely. But to people who have benefited from Elvish slavery, absolutely not. So these things need to be gradually pushed one way, or there will be a massive civil war over slavery. And to be clear, these are the views and opinions of the people who live in that world, not mine.
Even right now, there are quite a few people who hate Cornwall for taking their slaves away. Cornwall is improving an Elf's quality of life by forcefully removing them from terrible living conditions. Even Cornwall's views are radical to those who would prefer Elves to be the way they were 20 years ago.