- what are the processes involved

- what skillset / knowledge is actually required

- which libraries or game engines are needed for making this kinda stuff

- how long does it take?

You should mention on the help screen that the scroll wheel lets you zoom into first person/ engine hood view. Before you do that, those should be fixed though: The front shield is black, not transparent, so I could use only engine hood view. This is a bit too "dynamic" though, in lack of a better term. When you drive upwards, the camera descends below the engine block and I see the front suspension. When driving downwards, I look in the sky and can't see the car at all, makes avoiding obstacles difficult.

For the roads: To make driving a bit more challenging, add obstacles close to the road, e.g. guard railings.

For the generation: Right now it feels like a very even distribution of item scattering. Defining some types of areas and how these get populated with scenery may give a sense of "overall structure".

As a fan of Slow Roads, I do like this approach! Climbingin the mountains and jumping down was kinda fun. Maybe add a second car that is faster?

Well I hope you sell a lot of plugins so you can keep working on this :) Bookmarked and looking forward to updates.

Going offroad I discovered some nice physics like hitting a small rock at speed and it bouncing along beside me for a few seconds, or nearly getting stuck on the lip of something resembling a volcano.

Only suggestion would be somehow making finding the way back to the road easier when you get the other side of a block like a mountain range.

I'm impressed that I wasn't able to drive into a void, a lot of times I see things like this and it's a single generation pass that ends after 2 minutes of walking. Is it infinitely generating in chunks?

Also what is the goal of the game? Is it a driving simulator, like ETS?