I took a break from this for most of the weekend. But here's an update.
I reduced the motion of the two flaps adjacent to the gap by exactly half. This fixes most of the issues with the sprite, at the cost of some smoothness of animation. I'm NOT going any farther than that, because I believe I've hit a pro/con balance and do not want to ruin it.
I feel like I need to explain what my exact intentions were behind the dress motion and why it looks the way it does. I didn't want to base it off the in-game, 3D animation, because that has nearly no motion and is boring. Instead I based it off the BW regular Gardevoir animation. I wanted the dress to kind of "cascade" from the front to the back. From the front, this means the inside flaps move first, then the outside ones, while on the backsprite this is reversed. In order to make the dress move like this, the pieces on the left need to move to the left, and vice versa. This makes a gap in the dress somewhat inevitable. In addition, the motion of the dress from the back is noticeably less extreme, because those parts of the dress are resting on the ground and are more resistant to motion. I could have potentially made a simple right==>left and left==>right motion for the front and back respectively, which probably wouldn't have had these issues, but I feel like that wouldn't have been as good. The dress would have looked too flat when it's actually three-dimensional, and it deserves to be animated likewise. That was part of the reason that this sprite was by far the most difficult one to animate so far, even considering that this one hasn't gotten a rare animation yet and others have. I'm not goin
The above things considered, does anyone still have issues I should take care of before finalizing the frame rate and the new colours? Actually, I do have a couple of possible minor changes in mind (I almost always do), but I still need to know what everyone else thinks.
EDIT:
Hollymon, because the shiny version has its dress split into both black and white parts, it's impossible to recolour the regular version to shiny. Likewise, the reverse isn't impossible, just change both the black and white parts to the right colour.
And might as well edit in more responses, it would be easier for me to keep track of if I have it all in one post.
Ridaz, sorry, but I don't think I can rationalize adding the legs. It just seems kinda...weird. They're so thin anyways I doubt the difference would be all that noticeable.
princessofmusic, I recall a while back you said that only Zekrom is as dark as Gardevoir's dress. Actually yes, I did base it off of Zekrom's colours. The reason behind that is that it requires a whopping five different shades in order to properly show all the shadowing in the non-shiny version (regular Gardevoir uses four shades of grey with a black outline). As it happened, Zekrom was the only sprite I could find that had enough different shades to be used it as a reference. I could probably go ahead and try something lighter though, colour changes aren't that much trouble.