Very cute and creative! The sound and art are fantastic, and despite their simplicity, the fishing minigames were fun.
I think the "idle game" design somewhat takes away from the experience - I had to walk away from the game for a couple minutes during the latter half of my playthrough, and when I got back, I just had all the money I needed to reach the ending. It didn't really feel earned.
While I get what you were going for with the ending, it didn't particularly resonate with me (perhaps in part for the above reason). In terms of just fun, I think the factories detract from it slightly. By reducing the amount of fish, you reduce the amount of minigames you get to play. I think I would have liked to see the factory have its own minigame to maintain the level of fun the game started out with for the rest of the playthrough.