In retrospect, I think a better option is to only prerender the tree trunk, and have the entirety of the foliage rotate in the wind like only a few branches currently do. The way to do this might be to apply a more subtle rotational effect to the branch images than what's currently being used, and then on top of each branch throw a foliage layer that looks like it's rippling in the wind by applying a sort of a rippling pond distortion effect over the foliage image. That way there would be no playing of 2d animations on the map, and you wouldn't have the odd mash up of rustling leaves with still leaves that's currently in the game. I'd especially like to hear your thoughts on this idea.
With that said, here are some more comments about the 2D animation idea:
I don't know why more than 10 seconds would he necessary, as it stands it's a static tree with some slowly rotating images of branches. I think this looks less realistic than a tree rustling for 10 seconds and then playing the video in reverse for a total of 20 seconds of relatively fluid wind motion.
I see your point about overlapping shadows and trees. Do you think it would be possible to record 10-20 seconds of all dynamic assets on a map as one super high resolution video, then split that video into smaller segments that only play when they are within camera to keep system requirements relatively low? The dynamic video would be a layer above the static map. Maybe that dynamic layer could have it's own simplified static depth map so that characters are shown either above or below parts of the dynamic layer depending on their y-coordinate.
Right exactly, padding and dropping frames. However, I think deltaTime can only give you a reading of how fast the previous frame took to load rather than how long the current frame is taking to load, and that number could fluctuate much more than an average, which might lead to less fluid animation. I don't know, I guess it is something which would have to be tested out both ways to find what looks better.