I actually think if there is a rematch then Franklin will beat Silva. You hit it right on the button when you talked about Silva's take down defense. Silva is a black belt in BJJ so i think Franklin thought taking him to the ground would be a bad choice and thought he could trade with Silva. Silva got taken down by Lutter with one of the most sluggish take downs i had seen.
Franklin is one of the smartest fighters in the game. I thhink if there is a rematch Franklin will look to take it to the ground and lay some GnP on SIlva. If Franklin mounts silva i think it would be a whole nother fight then when Lutter mounted him.