I think the main “gap” might be the late 50s, when the cars started looking more and more like proper sedans, but before they adopted the boxier style of the 60s landbarge we have.
We currently have Kubby’s Cadillac as well as the other fairly large sedan that was added recently that IMHO fit fairly well for the american styling of the early 50s and late 40s, with the upscaled Moris Minor also fitting decently well for the stuff from right after the war.
A car I think might be a good addition would be something like the 55 belair, with the ability to morph the headlights to fit two round headlights side by side, which was fairly common a few years later.
It’s a very recognizable shape, and probably the easiest body of that era to create something that looks decently generic, since later models from the big 3 started having more and more complex front and rear ends.
Edit: I also agree with @Awildgermanappears for the 49 ford, an other very recognizable amd simple shape that’s also represent it’s era very well.
these are just suggestions, however I think they would give a good idea as to the changes between the time periods. Some of these would fit into other categories (mid size-full size etc), however its important to remember at this time the more expensive cars were physically larger then their cheaper models/brands. For example a 1958 chevy del ray is physically smaller then then the larger impala which also is smaller then the oldsmobile 98. The Buick Limited that year was longer then every gm model except the top line caddy. While the lesser models (special and century) were the same size as the small olds. The Super and Roadmaster were the same size as the large olds. So a basic body design allowing for stretching the passenger compartment and rear end would suffice for most designs. The small bodied cars on the other hand tended to not be stretched into newer models.
I’d suggest the 1940 Plymouth range, since all the cars except the Deluxe 7-Passenger Sedan and Panel Delivery have the same wheelbase and front end but offer a lot of body styles. It would fill the gap of early 40s American midsize bodies quite well.
I second that for early 40s. Maybe not copy them, but make a basic body shape similar that can be morphed closely to most of the major 3 companies designs is possible. Also remembering to have a alternative body design to choose from say the Pontiac or Mercury lineup for the same time frame.
If we are talking about old cars then I would like to see a Ferrari Dino or Lamborghini Murai style body. The one in the game is too big and can’t fit very good engines.
I fully agree on the need for 40’s, 50’s, and 60’s cars.
I’d also like to point out that it’d be nice to have some of the late 90’s, early 00’s aerodynamic compacts. And as I’ve mentioned before, it’d be nice to have something like the first-generation Insight and Prius, even if we can’t do hybrids, because the designs are very aerodynamic. Especially if they were given more than just their 3-door/5-door hatch variants, and were brought into a full lineup (2-door coupe, 3-door hatch, 4-door sedan, and 5-door hatch).
We could also do with a mid-90’s minivan. We currently have from the workshop one that fits late 80’s to early 90’s, and one that fits late 00’s from in game.
Last, and in my opinion, least important, we could do with some older two-door supercars.
You could probably mimic a first gen prius since it looked like a normal car, as far as the second gen goes… well, I don’t think I should say the word I’d use to describe it’s shape.
I know I’ve mentioned wanting to make one of those, but nope, it isn’t. You’ll just have to wait and see It’s something that never made it to production.