"I need to move on from sprite movies"
Meh. I had a twinge of hope when I saw the title...If you remember, I'm the guy who commented on the music from the first Tails GBA flash. Its a shame you decided to stop making them, but when I noticed the text above, I had a thought.
What forces you to make it a sprite movie?
If the reason for you moving away from this series is because you want to "move on' from sprite movies, then make a Tails GBA flash that you drew, or however you animate your stuff nowadays! That way, you can work on your animation skills, and please your fans, all at the same time.
And maybe, since it would be a graphical upgrade, it would be tails and his DS :P