Gotta recommend
Hero Express. It's currently on sale for less than $4 - if you're a fan of games like Trials and Elastomania then check it out!
Each level has you driving a different vehichle over different terrain with unique obstacles and it feels really good! The physics are the right combination of cartoony and realistic and each vehicle feels very unique! I've only played 5 out of the 11 levels on the map so far and haven't even reached the end of any one of them but am having a great time!
While driving you collect money to upgrade different aspects of your vehicle and it is immediately evident in the physics whenever you do so, which makes for a very satisfying gameplay loop as you save up to upgrade whatever aspect you believe will be most helpful to get you across the next obstacle.
I'm playing on Normal mode but there is also a hard mode which might offer differences in the routes. Currently at least some of them offer branching paths.
Also the superhero vs. monsters theme - each level shows a unique monster on the map and at the start of the level - leads me to believe something happens when you complete the track. Maybe a boss fight?
I don't want to look it up and potentially spoil myself but if this seems like the kind of hook you'd be interested in, by all means check a youtube video.
From my point of view, even if there's nothing at the end of the track the game is still worth it! Especially at the current price!
Support the devs so maybe we could get a sequel with even crazier levels, a level editor, and - my personal wish - perhaps even a richer story mode with missions that not only build on the excellent vehicle physics but also add a more fully featured world with additional types of gameplay in it!