Hi Yeeeee,
Thank you so much for downloading and playing Atomica! I understand your pain. As a developer, I should have been able to reach max score but really, it took me forever to get to that S Rank (37 tries actually, I counted each one). I had a friend who played it twice and got an S just like that. This is to me reflective on the struggle of life and though this may be a game, it is a game that doesn't have a discernible system to break as it is quite random, paralleling life's own mysterious system.
That said, there are strategies that can be employ to get a higher score. Something that is not yet highlighted in the game is the fact that at 10% Atomic Integrity (your health) or lower, the score is now basically double per hit - which means each time the ball hit a purple box, your score increases by 200. Knowing this, a possible but risky strategy is to bunch up the purple boxes with [space] (activating the gravity well] when Atomic Integrity is low. Doing this will allow for a final "burst" of score when the ball hits the core for that knockout punch.