The amount of cars you have, meaning themed cars. Like for example Pacific Ocean Park had the famous "Safari Dark Ride" and this had Jungle Jeep cars. While across town in Long Beach California at the NuPike there was the Laff-In-The-Dark ride which had Pretzel Cars, quite a variation. Then further across town is Disneyland Anaheim which had the Haunted Mansion Doom Buggies and at Mr. Toad's Wild Ride the Antique Cars, so it varies a lot by theme. But the more cars of various themes DR Builders have along with scenery packs to go with it and truly dark structures with custom lighting in rooms, the more they will be able to build. Anyone agree/disagree, lets get talking about this issue.