I have been joining Coders of the Caribbean and Code4Life competition and found that the animation is really hard to read.
Personally i have some sort of color weakness that affect my ability to distinguish Red and Green. As a result, distinguishing between Orange/Yellow, which are used as Player and Opponent, would be a very difficult task for me while watching any replay. The color issue also affect many other contest and practice questions as well.
According to wiki ,
There are around 10% of male facing these issue, so I believe that I not alone.
Simply changing the use of color into different set might again raise problem for different group of people. Therefore, i would suggest the following to improve the situation:
1. Provide several color theme of choice (at the setting page for the animation)
2. Allow picking different color for different team
3. Instead of color, use another feature to distinguish between teams. For example, add a pair of horns on the android, or having square head.