How do I think that Samuel would make a better Free Safety than Wilson? That's easy. Samuel likes to lay the wood and many have mentioned he is better in the slot than out on the edge. Yes, he's had some good games, but over-all, I don't see him as anything more than a #2/#3 CB. He's definitely not in the Ty Law or Patrick Surtain category of Cornerback.
Wilson has been somewhat fragile back at free safety and, as I said, seems to have become somewhat gunshy. We need a free safety who isn't afraid to hit people. And Samuel isn't.
Maybe if Wilson comes back and shows that he isn't gunshy anymore, I will change my opinion, but not until then.