Thanks for the extensive critique! You're right about the gameplay being lackluster. I designed it to just be a little distraction while the player watched Hadley flirt with cute visuals. The art and characters were my focus as you surmised. But even that isn't as developed as I originally planned. If I wasn't lazy I would've had more build-up to the ending and explored their relationship more.
You have good suggestions concerning the gameplay. If I was to flesh out the actual game of the game I especially like the idea of introducing more mechanics with each star. As of now objects and birds just spawn a little more frequently and it's not that noticeable.