This was really well-made and rfun! I got to level 3 before I accidentally blocked myself off (and died of social isolation?)...
I think it would be cool if you started with a set of tiles, and you could chose from that set as you played the level. Then every choice would be more of a calculated move between conserving good tiles vs reducing risk of getting eaten by birds.
I'm also interested in the ontological implications of placing down a tile in this world. In the beginning I thought we are meant to play as Puschel. Puschel is somehow able to will his surroundings into being a certain type of environment. The limitations of this power is that he must not have observed the area beforehand and it must be adjacent to him. This seems to show that Puschel is some sort of naive creator being. He is not omnipotent or omniscient and cannot make miracles (ex. changing a known environment from one type to another), but he can still effect drastic change on his local surroundings by wishing for certain things that inevitably come true.
However, now I think the more likely possibility is that we are playing as some sort of writer instead. We are writing the story of Puschel but, interestingly, we do not have full creative control over all aspects of this story (limited choices of tiles, no control over the birds, technically no control over Puschel although his behavior can be deterministically manipulated by ours). Playing the game is a mechanism by which we write the story of Puschel. Once a game ends, the story is written, and the structure of the world and sequence of events Puschel encountered become his fate.