This was a LOT of fun.  After making the initial pattern, I played with the Recolor tool.  

 

Then I decided to see what would happen if I started layering smaller diamonds on top of the original shapes.  Here's 1 additional on each side

 

 

Here's 2 additional on each side.  Also, playing with colors is really addictive.

 

Thank you, Helen!  You're an amazing instructor!