It's easy to look at this year's results and say Massa would have won under a medal system but it conveniently factors out that drivers would have driven completely differently if the 2nd and 3rd places they were aiming for as safe, points finishes (especially when they were on the first race for an engine) would be completely worthless compared to a win.
If you'd put Hamilton or Massa in the 2nd position on-track and said to them "win or nothing" Hamilton would be the driver you'd pick every day of the weeks and twice on Sundays to get the job done over Massa.
Likewise, I think we'll see drivers going for broke in terms of engine maintenance - taking the risk of failures, but knowing a failure earns them a free chance for the next race anyway. Winning only 1/3 of the races this past season would have seen a driver crowned champion.
This is the issue I have with the medal system: It'll reward ballsy driving for sure, but I can guarantee it'll cause just as many tears for failed overtaking or on-track spats or 'repaying the favour' from the last time your team-mate tipped me on a corner.
There might be more reward for the winners under a medal system but there is an even greater opportunity then to hinder or affect your competition's result (or 'supporting' your engine supplier).