After providing feedback from Wayne and my colleges, I did the animation again based on those useful comments. At this moment, I am satisfied with it although it could be better if there is more time. During animation session, I found some difficulty in using animated texture. Fixing this MAYA technical issue is time consuming for me because of lacking 3D experience. Fortunately, I eventually got a good tutorial which solve the problem by using image sequence.
Anyway, the production must go on. The schedule said that time for animation has ended. Thus I have to keep moving to lighting process.