Playability:
Not really playable but you do have the bones of a bunch of mechanics here. I would continue to work on this and not be hard on yourself throughout. You got this dude.
Theme:
Not feeling much of the theme here but that's fine since it was unfinished.
Cleverness:
Interesting seeing this move in the direction of a builder or defense style system. With no Design Document it's hard to tell what the goal was but this seemed to be the direction you wanted.
Artistic Style:
Simple and consistent pixel art with great use of dithering and detail where needed. Nice work.