I know its going against the grain here but TBH I would prefer fastpass was NOT impletmented.
The reason being we all want these games to be realistic, however there will come a point where the realism of the game is so great that it becomes a chore to make a successfull park and the game will lose its charm and fun, and I just feel a fastpass system will go a step to far toward that. Plus to have a successfull fastpass system in a park you need 10,000 plus guests in for it to be worthwhile, look at real life parks around the world, if you walked into Disneyland (where fastpass is free) on a day where the queue levels were as low as they are in PC, fastpass would be deactivated, and if you walked into six flags or alton towers (where you pay for fastpass) on a day where queue's were that low you just wouldnt buy it.
There are plenty of things I would like to see implemented/improved/perfected before the devs went anywhere near fastpass systems or single rider queues etc.
I know its all personal opinion, but that's my twopence