Played this for a little bit and I can see some real promise here. But I did have some trouble with the framerate, I'm guessing that's just because its a web build. Also another note, the game starts out really fast paced so it is very difficult to understand what to do in the beginning. I didn't really have time to understand the upgrades and how purchasing them worked. So I would either start the player and enemies out at a lower speed, or decrease the amount of enemies at the beginning to something like 2-3.
Other than that, this game looks very polished well done!