Antonio Brown is an interesting choice for HC. I'm not overly impressed with their choice for GM. IMO a GM needs a strong scouting background like Holmes to be successful or groomed for years like DeCosta was groomed for the position with the Ravens by Newsome.
I think McVay could be a good GM if he spent a year or two as Snead's assistant GM. He would be in instant demand if he spent even a year as Snead's "assistant" and let it be known that is what he wanted to do. A successful tenure as a GM would cement his HOF credentials. His biggest asset is he understands the importance of culture. He already works very closely with Snead on most things.
Most see him in media, but I wonder if he would find it boring and not challenging enough.