Agreed, but due to limited time (I joined a team halfway through the jam to replace a disappeared dev) I couldn't think of all possibilities.
There are many implemented, I just didn't want to go overboard. There are sfx, enemies flashing on damage, and even hitstop (time slowdown) and camera shake effects when you get damaged. I obsess over the small details and effects like this :)
Definitely can be tuned better but if you saw none of them it could be a browser/WebGL issue of sort.