This game could really be quite good, but many things could be improved. The idea is really great, but a few things should be taken into account:
-The music; pretty gay, and repetitive.
-Ball speed; at the beginning, very very slow, and you arent bothered to speed up until the second stage (4 paddles), and you screw up. Add physics; make the ball faster each time, although don't have huge jumps in speed
-Gameplay; a bit repetitive; you can just stand the 4 paddles in the same place- add powerups, coins, etc
-Score; don't have it sprint at some points- have a continous flow of points, or extra points for each hit/powerup
Personally, I think this would be a very good game, but some more ideas have to be taken in.