Something that I think would be really fun is to be able to buy/craft vehicles with multiple occupants, which would make traveling around glitch faster and even more fun. Some of the faster vehicles could be more expensive to maintain, and they could run on gasoline made out of general vapor.
For example:
Bike: 1.5Xwalking speed , seats 1, no gas needed
Tandem Bike: 1.5Xwalking speed, seats 2, no gas needed
Golf cart: 2Xwalking speed, seats 3, tiny amount of gas usage
Small Car: 3Xwalking speed, seats 2, small amount of gas usage
Normal Car: 3Xwalking speed, seats 5, moderate amount of gas usage
SUV: 3Xwalking speed, seats 7, large amount of gas usage
Boat/Canoe/Kayak: For traveling new routes between different continents that are separated by bodies of water. Seating, speed and gas usage depends on boat type
Airplane: Flies! Seating, gas usage and speed depend on type of plane (but generally speedy and huge amount of gas usage)
UFO: ?!!?
I have no programming knowledge and this is probably difficult to program, but just throwing the idea out there! :)