I do like the simplicity of it! I also found it enjoyable to try and predict where the spikes were going to be, so having the bubble around the player, I felt really added to the gameplay. One of the things I found a bit odd however, was the rotation on not only the z-axis when you move (or at least that's what I assume to be the case), It had a bit of a warping effect when paired with an orthographic camera. Other than that though, a really neat concept that was executed well! good work!