Heh, pretty cute and inventive idea! I thought this felt a little more like work than like playing a game to be honest, so I only skimmed the levels. Wonder if this could be gamified a little more?
Yeah, I thought to add a timer, but I prefered it to leave the mood more in a more chill level progression and let people get creative. There are some things that could be done, to make it, e.g. more passpartout-like, for example.