Definitely an interesting idea being explored here in general, although the link to the theme is extremely tenuous in my opinion as the 'scale' isn't really affecting the gameplay or decisions made by the player. The control scheme wasn't really manageable because the mouse cursor didn't wrap around screen edges and it took me several shots before I realised there was even a power meter on the right.
I think a tutorial or even some UI text explanation would have greatly helped the overall approachability. Well done for getting a working submission though!