I like the graphics and how smooth everything looks.
The core gameplay is solid, steep learning curve, hard to master.

However there doesn't seem to be much reward for mastering it, other than seeing a single number go up.

There is no sense of progression other than having the playing field shrink, but the game was so unsatisfying that I never got to seeing it shrink too far.

Would be a really cool game if you added some upgrades, a system to unlock those upgrades, different enemy types, power-ups. Any of those would do.

Just to encourage players to play until they've gotten the hang of it.