I just had a thought that would back up them not having the time to do this. As far as I know, they have been trying to also give AF unique effects.

Touched up on in the live letter. Yoshida said that the developers told him it is extremely difficult for them to animate the WHM hood to toggle up and down and that it might not happen in the end.

Perhaps this project started out too ambitious and then had to be condensed into something more manageable. Multicolored animated gear for this engine actually sounds like too much work. This is another big reason there is a new engine being developed, but that's a different story entirely.