There's no "regular steering" in this game but drifting, there's a functional difference between them
Idk if it was intentional, but the boost mechanic compensates the drifting slide so that you may save yourself from crashing to the sides from time to time, like to kinda course-correct from the offset caused by the drift
About the cargo, initially it kinda seemed like a completely useless factor, but then I understood, it's a pretty unique "HP-ish system", or at least that's my interpretattion
With ramps, I noticed that it kinda forces the boxes to stay in their place, but this isn't consistant, they sometimes get blown away (as I'd realistically expect) or, in even rarer cases, the truck would touch the ground with its rear and explode; I kinda like but also kinda dislike the random outcome that may happen when taking ramps
Many levels felt annoyingly long, and while level length certainly technically could count as a difficulty factor, it does bother to have to start all the way back each time
It looks charming but I'd suggest to let the user adjust shadows, or maybe even be able to disable them; the game ran smoothly in my side but there were times I had to switch tabs and sometimes this would cause a lag that would last for a while, and while that's not a reason for me to lower graphics quality, I can easily imagine some users not sharing the same luxury to run the game in a playable state
(As soon as I wrote that, I checked on reviews, it seems like I'm right)
Shadow casting is expensive on resources, it makes a massive difference when getting rid of them, some games need shadows as reference for the player to move properly, but in this case they don't really seem necessary to play, although without them, I think this game wouldn't look as pretty
Mayyyybe you could also try light baking and then only have the truck and cones cast shadows in realtime?
All in all, it's a nice-fun challenge with nice visuals