The one thing I could see happening with a prime-time reboot is, on top of a refreshing of the set design (bringing it more in line with the UK set), a 16th question that's a free shot for $2M.
Now granted, I'm playing with money that isn't mine here, but it's a big way to set the show apart from previous runs. I mean, you'd have to win the million first to even have a chance at the double, which is not likely to be an easy feat, plus you can add the stipulation that there are no lifelines allowed even if you had any left.