nice movie..
One of the best sprite movies i have seen, u did a great job so i'll go right away to the things i think you need to improve on.
1.The clarity of backgrounds, maybe it would be a good idea if for your next episode you should trace the backgrounds so they wont look so blurry at times.(also i think you should redo the one where we get this view from behind sonic, it looked all cut out)
2.Try to avoid the hand drawn stuff, it just doesnt look good doing a sprite movie and add something you drew to it(blood,tears,etc)it just feels out of place.
4.Pay more attention to ur perspectives, that last one with the robot army could've been better
Like i said a really nice movie, and well it's funny how i wasn't the only one that thought having an army of enemies would be cool...lol