Thanks for trying it!
You can hold down left mouse to shoot automatically, but I am going to add an toggle option since Myrmidon doesn't really lose anything by stopping attacks. The second character gains damage & loses speed for every continuous manual attack, so it's an option because of gameplay variations like that.
I'm definitely going to make the shopping pause infinite & activatable at any time, since that's a common complaint and a bit buggy anyway.
Rat wave density will go down, since that was just a test on pattern spawning, and I'm going to tune damage across the board with enemy HP since I haven't given that any work yet.
Losing gems to the bottom of the screen is a common complaint, but it's definitely something that requires some strategy the player movement. I think I'll slightly increase the base pickup range & make its upgrades more effective, as well as some uncommon "powerup" drops that will suck all gems towards you.