I know right. People have been begging for GCI trains to make GCI coasters, and now when we got them we can't make GCI coasters! Even the classic woodie has way more friction than in real life. Even those 80 year old coasters run smoother (They even need a brake-man else they would go too fast!).
But really, all coasters in the game have too strong overall friction. To me it looks like they just lose way too much of their momentum (trains are too light?).