The reason why you aren't getting an answer is because it takes inspiration from 80s German cars, but it is not based on any.
Had anybody seen the blog lately? http://blog.beamng.com/something-is-still-on-the-horizon/ SPOILER ALERT! FREAKING CAMPAIGN MODE LOOKS LIKE THE COOLEST THING EVER! WOW! It really reminds me of the legendary SLRR game! The garage looks so cool and the comic style characters are so cool! ALSO THERE IS PLANNED VULKAN SUPPORT! HYPE! HYYYYYYYYYYYYYPE!
Not really, if an update is big enough it might skip a few version numbers. E.g. 0.4.3.2 was the current version a while back (November) and the next update was 0.5.
They usually release their new updates every 3-5 weeks, so whatever content they have ready by then will probably come out. So if they get 4 updates worth of content in the next 3 weeks, that will be fine then. But they could always do it in small releases and go up by 1 version number at a time.
West Coast USA will be the first official map, possibly even first including mod maps, to include a proper full and finished city! I wonder what the houses in suburbia will look like? Hoping they are similar to my neighbourhood