Hopefully you guys are currently working on rebalancing the car designer, so here’s a couple of my own suggestions that you might consider.
Economy
Economy seems to be massively underrated. It’s easy to pick all the cheapest, least efficient choices in the engine designer (12:1 AFR woo!) and still be highly competitive even in Family, Commuter, and City Eco markets. Even in Fruinia cooling flaps are almost always a bad investment, but in real life they are becoming more and more common. Cooling flaps should also cost much less than they do now. Also, you can set aero quality to -15 with no competitive loss or even a gain due to lower cost. (side note: why does extra aero quality add material cost and not ET? I would imagine extra aero means more wind tunnel testing.) The other effect of underrated economy is that excessively heavy cars are not penalized at all. Which leads to…
Safety
The impact of weight on safety seems to be somewhat overrated. Currently the best way to make a family sedan is simply to choose the cheapest, heaviest parts - steel panels, iron block, etc. This feels unrealistic, as in real life the focus is on reducing weight with aluminum and other materials. I’d probably put a slightly greater emphasis on footprint rather than weight, which would encourage using more expensive materials to design large but lightweight cars. Also, safety in general seems to be slightly overrated. Choosing advanced safety is almost always the best option, even for the Light Sport category.
Transmissions
Automatic transmissions seem to have too big a loss in efficiency and 0-60 time. This might be OK for the old automatic, but the modern lockup automatic should have efficiency and 0-60 times approaching manuals. In return, all automatic’s drivability and comfort bonuses should be slightly reduced, since they are currently OP for many demographics.
Dual-clutch transmissions should receive a significant drivability, sportiness, and comfort boost over single-clutch automated manuals. The nearly instantaneous gear shift means torque delivery is not interrupted, which improves drivability and comfort. Also, the faster shift should also improve sportiness. Currently DCTs offer only a minor 0-60 bonus for a heavy cost in PU, ET and reliability.
Seating
Currently, seating capacity only plays an average role in the practicality score, while in real life, it is one of the most important numbers that defines a car’s intended market. Seating capacity should be an independently scored market statistic, just as quarter mile time or top speed are for certain markets. For example, the family market should have a high weight on seating capacity. Real life family vehicles like minivans and three-row SUVs have large seating capacities that are not rewarded in the current version of Automation. And non-sporty luxury segments really should have at minimum 4 seats.
Also, I believe that bench seats with 3-person capacity should not be more expensive than bucket seats with 2-person capacity. Usually, “captain’s chairs” are an upcharge over bench seats in real life, not the other way around. The comfort penalty of bench seats is fine, but the cost should not be penalized.
Practicality vs. Prestige
The practicality vs prestige dichotomy seems flawed to me. It results in the best luxury cars being mid-engined 2-seaters instead of the sedans and SUVs that really dominate the market. Less practicality should not be equivalent to more prestige; less practicality should result in more sportiness. Think about it: the Mercedes S-class is more prestigious than the SL-class. But which one is more sporty? The BMW 3-series and 4-series are nearly identical except for the number of doors. Buyers don’t choose the 4-series because it’s more prestigious, they choose it because it’s more sporty.
Also, the 500L limit to cargo capacity’s influence on practicality seems too low to me. It kind of makes a lot of SUVs and wagons useless compared to hatchbacks. Would it be possible to raise the limit to 1000L, but make the second 500L be less beneficial than the first 500?