Figured out that if you right-click to clean up the debris and reach 100%, you can clear the stage! However, since it ends pretty quickly that way, I felt like it could use a lot more playtesting.
Also, the title says to press 'E' for the shop, but it was actually 'B'. Plus, pressing 'B' kept toggling the shop screen continuously instead of just opening it once, so I'm pretty sure that's a bug. Using the mouse to click the SHOP button worked fine, so it'd probably be better to align the keyboard input with that.
I bought all the shop items, but maxing everything out happens way too fast, so the balance definitely needs some work. Also, even when maxed out, the heavy bullet felt weaker than the 3-way one. Might want to tweak those numbers too.
Since you need coins to defend against the aliens and go to the shop, the vacuum requirement needs to be lower. Otherwise, it hurts the overall game balance and fun.
On the other hand, the idea of right-clicking to vacuum and CLEAN things is really neat. It fits the space debris theme well, and I thought that concept was great!
Lastly, having some BGM and SFX would definitely be nice—it feels a bit too quiet right now.