The Theme, mhh not sure if it really Matches since the way out seems to get to the Finish Line.
Hyper Casual Game with a bit more work it could be a interesting mobile game to spend some time on.
Sounds would be nice
At some point the Speed of the Cube is such high that it just don't collide with the Objects so you glitch through.
Check your Rigid Body on the Cube about Collision Detection.
If its already on Continuous you might try to make the colliders a little bit bigger