Interesting...
Well, I'll say this now; this isn't a good Sonic movie. The problem didn't lie in the art (which was great, it's hard to draw Sonic et al), but the problem did lie in the voice acting and the concept. I'll cover concept first.
It was a neat idea. Neat as opposed to good. The premise for a flash series based on the everyday life of Sonic the Hedgehog will only work if the jokes are fresh and relate to the characters they affect, and if the voice acting fits. In this case, neither necessary element was present. The jokes weren't as funny because they just didn't fit the characters. Sonic is really not that great a hero, even though he does know what side he fights for, he often dances on the line. He wouldn't be nearly as patient with Tails as he was in this movie.
The voice acting was okay, but it was definately not Sonic, Tails, or Knuckles. Shadow sounded alright, whoever did the voice for Shadow passes the test for me, but the others would all fail. And it's not that the voices were bad, they just didn't fit. I think you should reconsider the characters. The premise works for a cast of completely original characters, who haven't already been in comics. You should even adopt the Sonic style of art. But my advice would be to drop the Sonic premise and then keep everything else as it is. It would be a much better movie that way, at least in my opinion.