I dont know if you could implement this, but if you could It would make the game much more challenging once again and without having to add more deviations or wtf shots.
I took this idea from the British Open and the fact most of the players were saying the fairways were just as fast as the greens, if not faster in places. I dont know if this would be possible but could you tweak the fairways at RSG and St. Andrews so instead of playing normal, they are in fact the same speed as championship greens so when ball hits them they bounce and roll for miles just like in the open. If programming this is too difficult, at present there's many places (RSG 7 for example) where you might hit a bump in fairway and ball then bounces forward loads, could you not tweak the landing zone of our balls so It replicates hitting a bump more often (even if fairway is flat) and giving us a massive kick forward. This would bring the rough into play much more and you might have to think about drives more often and even check down to wood, 3 iron.
Holes where It would make them much more difficult with added roll or fairway's like champ greens:
RSG: Hole 2, 4, 8, 9, 12, 14, 16, 18
St Andrews: 2, 4, 6, 7, 12, 13, 15, 17,