It would all depend on what the Braves give up. If they give up Folty (2-4 WAR) and Inciarte (3-4 WAR) to get Sale (4-5 WAR) with Smith in CF (2-3 WAR), I don't think they will be a better team at all, and would project them for easily less than 78 wins.
They already project to have 2+ WAR from every pitching slot in the rotation. Upgrading one of those slots by 1-3 wins isn't going to be worth whatever they have to give up from the MLB roster to acquire Sale.
If it happens we can discuss what the bet will be for sure but it seems like you're hedging already after you just made a snide remark about enjoying your 78 win team.