LOL it kinda looks like u used aftereffects but then I saw the dithering and I could tell that was photoshop. I had to use aftereffects like 2 years ago for a course, I made this in a week : youtu.be/kiTAZ41M8p0 well anyways, aftereffects is really complicated at first, but it really is a great program. You should try and keep everything in aftereffects ( except for the drawing that youd do in photoshop or Sai, OBV) and just mess around with it. There should be a way to reduce the file without making it too ugly lmao