It reminds me of those stories of netherland bikers, really nicely done. The timer is actually a great mechanic in that context and synergizes with the theme and gameplay. The problem with it though is that if you screw over early you can as well just restart.
I got to the level after the cat encounter. Jumping around on smaller tiles is too much for me. Still, being able to finish a level after time runs out is an 11/10 decision, as it allows player to take his time to practice the level that's problematic for the next playthrough. Was this intentional?
At first I didn't catch the shift mechanic until I tried my second playthrough. It would need a more forceful tutorial. Now I see that it's a lifesaver around vertically driving bikes and requirement for later levels.
The shift walk mechanic is useful but I'm not sure if I like it. It screws with player offset while estimating step distance. Normally if it was a grid based game it wouldn't be a problem, but now you have to adjust your position on the fly in combination with quick decision making around bikes and on the ships. The perspective doesn't help here, as it's hard to quickly tell how much I need to move the player.
The game looks really nice, but the shadows absolutely suck for this kind of game. Bike shadows will screw with my eyes and it's hard to tell where and how many bikes there are with peripheral vision.
I don't like bikes turning unpredictably. There should be at least some tell before that happens, otherwise every bike seems like something you shouldn't even stand close to in a wide radius. At least spawning is telegraphed.
It's hard to get used to the randomness because many levels are puzzle-like, but I like it that way. It's a beautiful chaos.
The car survival can be cheesed by positioning yourself around the edge just where you will need to go through. I would get filtered there otherwise.
I like it overall, good design all around. It probably needs some other failure state (while trying to leave the timer in) that wouldn't have me replay all those levels.
You should really add sounds, with doppler effect if possible. I can imagine the cacophony being kino.