I'd give it 4 if it felt more complete and didn't have so many flaws.
First off. Sound. You really need sounds.
When I click through the stages I finally get to the end screen. Wtf? And choosing stage by clicking the paddle just feels odd.
I can pull the paddle outside the borders. Intentional or not, this just seems like e bug.
The graphics explosions on fireball is to slow, and for through ball way to slow.
Sometimes it feels like the ball bounces at a really strange angle, and I got some strange effects when having extreme angles to the paddle.
This could have been a good breakout clone, but it feels way to sloppy. Put some more effort in it. You lowered the grade from possibly 4 to 2 with this.