Physics and graphics are nice. Music is a minus. Would be better if levels were unlocked or played in progression. And last, most important for me thing: it's a platformer, not an adventure game!
You actually made me play all 6 levels and the Bonus level!
Please change the music, or give Option to turn it off.
It s not clearly visible if the ball lands on the Grey or on the dark grey surface, this makes things harder than it has to at times.
Now for the difficulcy:
Add an Overall timer for a speedrun (maybe post your own best time as a reference)
Add a Maximum-jumps-counter, to lets say "finish level 4 in not more than 5 jumps" or something :D
It was kind of enjoyable. I don't like how every level is playable at first though. The physics blow, totally like, completely. That WAWAWWA sound in the music annoys my soul.
Just fix those things.
OH AND THAT DAMN CAMERA.
what is it doing?
You need: Background, longer music that isn't as repetitive, mute button, animation for main character and the "bad guys", diversity among the "bad guys", much, much longer levels, some in-game back-story. Also, if everyone can skip to the last level and "bonus" level, then why should we play the ones before that?
no story, cheesy graphics....... Nope. You need to develop it more (way more)
There are thousands of games like this on NG. All you have to do is go search 'ball'(whoops XD)
and you get hundreds of results, but much more advanced games.
I'm sorry, but this just doesn't show much effort. Keep working on it.