Thanks a lot for playing! Do you mind if I ask how far you made it through the game? As for the number of aliens killed equaling stars achieved for a level I've struggled to decide if I should directly call it out or not as how that works! I'll consider adding an explanation in the game! The instant retry was a huge bonus in frustration levels for players and was definitely a core design philosophy. I also think the game tends to feel more natural and less frustrating on a mobile device which is our targeted platform. I will definitely add a try button on the level complete screen! Thanks for giving such a detailed review!