Great idea! I was like Woah! when I saw the breakout concept reversed.
Artwise, the game looks superb! It feels polished and the music goes well with the game!
The gameplay is great too. At first, I built a wall near the planet and thought that's it! I can replace the blocks destroyed by the ball and go as long as I want but, the difficulty increased and it really got me in the end. So I think it's perfect :D
Excellent Job!