Matt/Steve
I know several of the jurors. Bucky Barnes and Bruce Banner are men that I've known for years, who are committed to trying to help people. They're Avengers. They always will be.
Sam Wilson is the Sam from your world, I believe. I'd trust him with my life. He's committed to doing the right thing, even if that's not necessarily what the law is going to dictate. I think that's important. Especially while we're still forming this Constitution. You're on a jury that will have a say in writing the laws moving forward. As a lawyer, I know you appreciate that. If I had a vote, he'd have mine.
Hank was part of the team that drafted this constitution, to begin with. He's easily the smartest person we have here and I would be hard pressed to find a reason not to want him to continue to have a hand in the drafting of the document. He'd be a great choice.
That said, it looks like Cosima and Xavier are the front runners. Of them, I'd have to go with Xavier. Cosima made some decisions that upset people in the past, namely, Princess Leia. Xavier has experience shepherding large groups of people and has earned my respect, even when I disagree with him. So between them, I would want him to win.