The sounds are amazing! The crackling, your own voice when doing something wrong or right.
I was stuck on level 7 for a bit, until I figured out I could sacrifice one of the blue dots. The only thing that was mildly frustrating (because it played in my favor in the end) was that on an intersection the virus would make a seemingly random choice to go left or right, and I couldn't really come up with a plan, because the choice of the virus would vary.
But I really enjoyed it and played it all the way through, great entry!