You got the recipe for a good roguelike, there are some changes i would suggest though.
Attacking while holding click, moving the camera a bit so you can see what's behind you, a shader or something to highlight upgrades behind walls, and a more refined visual feedback for attacking, which was kinda confusing to me as both the sprite and the vfx are meant to do that but they pretty distinct animations.
Overall, i can see this turning into an actual commercial game👍