- ESC is used by the web player to cancel fullscreen. So avoid using it for the menu, use something like P instead. Currently you can only open the menu if you go out of fullscreen.
- Was hard to know if the upgrades were working because the UI doesn't show cost and your points don't update reflect what you just spent until you close the menu. That's a common symptom of the not letting the UI widget update while the game is paused. You have to set Process -> Mode to "Always" on the Control that handles and shows the points
- Probably the quickest way to improve your gameplay would be to make the enemy spawns get faster over time. Just keep track of time since the game started and use that to determine how many/how fast to spawn enemies. Right now your game starts hard then gets very easy quickly. It should be the other way around.
- I didn't know I could move with WASD until the very end. Maybe that's just me being dumb lol But I'd add that to your itch page anyway just to let people know.