What a fun little game; an absolute blast! And, of course, the original soundtrack by Dāku is phenomenal!
I'm really torn on the issue of difficulty and goals. After having spent a good chunk of time to clear level 3, I think the mix of caution and speed being asked for is... fairly reasonable. It's a good difficulty for a game you're willing to sit down and grapple with. I was quite engaged and satisfied as I gained a better understanding of what the controls were asking of me.
That being said, it is still a bit jarring that the specific mixture of score + clear is the only goal at stake. It might have been wiser to have pure score, pure time, and the original score + clear represent three different methods of clearing stages, each with their own associated goal, score, and "medal."
Most of the core problem with difficulty is in telegraphing and memorization. The levels themselves are fine—I think, anyway—but there's a lot of time spent trying to parse and memorize level layouts that could be cut down in various ways. Maybe each level could start with a little map and camera overview (that could be skipped, of course). The houses could emit smoke to increase their vertical sight-line. A bunch of little touches.
That said, level design polish is easily the hardest thing to do in 10 days, and I think the final result is still a reasonably understandable—and deliriously enjoyable—experience.
Fantastic! Great work!