The designs of cars of any era reflect real world events and conditions. Laws are passed that change aesthetics or performance, such as the requirement of side marker lamps or that of airbags.* Resource availability also has effects, such as the shrinking weight and power after the oil crisis of 1973. Cars are also affected by trade agreements, the wealth of nations at any one time, technological and engineering capability (such as in steel shaping, etc), and a myriad of other environmental conditions.
Including this sort of dynamic atmosphere in the tycoon mode was a brilliant move on the part of the game creators, as that will allow people to work their design magic under a myriad of different conditions, with different resources to work with and different requirements to work within. It does however provide for a rather stale sort of repetition on replays, and even makes it unfairly easy for the player as they are aware of the way the conditions of the world will change in a way that rival AI automakers are not. I have an idea that will not only fix these problems, but will also lead to more ingenuity in design, as environmental restrictions will be dynamic: Random History Mode. In this mode automotive technology will progress, just as it did, and countries will write laws, just as they did, but the order in which technology progresses and the specifics of the laws being written will be somewhat randomized.
Imagine the differences we might see in today’s cars if CFRP was invented during the 50s, or if battery technology progressed much faster than it actually did, or if the car culture in Italy evolves around completely different ideals, etc.
This isn’t a completely fleshed out idea, and having not yet played the game I might be suggesting some things that would be very hard to implement without being aware of it, but hopefully something of this sort will be included in the game so that replays don’t become stale, and designs don’t either.
*When automakers in the US were forced by law to include side marker lamps they started by sticking an unattractive yellow rectangle on the side of their cars. Eventually however they realized that they could incorporate them to the design in much more attractive ways by doing things like creating wraparound headlamps with side marker lamps included in the whole assembly. This ended up affecting headlamp designs all over the world because the US is such a big market even for non-US based automakers.
Airbags had a wide effect, not only increasing the weight and cost of every car, but also removing some of the edge certain automakers had over others by from including what was previously an optional safety feature.