My eventual goal is to add RPG elements, such as characters to speak to at stations, quests to deliver goods, and unlockable exploration of a railway network.
The short-term goal was to implement the difficult bits first (track-following, wagon collision) so that me and my son can work on the interesting bits together!
Potentially, then there's the possibility to drive different ones. I've always found it interesting how in Thomas & Friends, the engines are their own characters. In earlier books it's more vague how much control the driver and fireman have, and to what extent they're wrestling with the personality of the engine. In later books and TV series, the drivers may as well not even be there, it's practically the engines themselves driving around and talking to each other.
