Thank you very much for the feedback!
Yes, I was thinking of adding more combo effects. Perhaps also changing the background when the combo exceeds a certain value or invert the screen color. Also making the combo count bigger and center.
I was considering creating a branching story based on how the player handle ads bubbles. There would be two branching points, resulting in four (bad) endings. The first few levels would be identical for each branch, and after that, you would discover information about the person you are helping. Each ending would feature a different character (each with its own gameplay variations and difficulty).
Each ending would show a light of hope growing bigger, and after experiencing all of them, it would unlock a fifth story with a good ending.
However I haven’t got all the details ready yet 😅.