<Extended Excel Color Code Palette>
1. Light Blue - 
                            
                            #A4D6E1
                         - A soft, calming blue that provides a gentle contrast against black text.
2. Light Green - 
                            
                            #C6E1B2
                         - A fresh and vibrant shade of green that is easy on the eyes and stands out well.
3. Soft Yellow - 
                            
                            #F2E6B4
                         - A warm, sunny yellow that adds brightness without overwhelming the text.
4. Pale Orange - 
                            
                            #F4CBAE
                         - A light orange that conveys warmth and positivity, complementing black font nicely.
5. Light Lavender - 
                            
                            #E1C6E1
                         - A soft lavender that introduces a subtle touch of color, creating a serene atmosphere.
6. Light Gray - 
                            
                            #D3D3D3
                         - A neutral light gray that provides a clean backdrop for other colors and ensures legibility of text.
7. Mint Green - 
                            
                            #B2E7D6
                         - A refreshing mint green that adds a cool touch and pairs well with the existing colors without clashing.
8. Soft Coral - 
                            
                            #F6B3A8
                         - A gentle coral that offers a hint of warmth, complementing the other colors while maintaining readability.

These additional colors blend well with the original palette, enhancing the overall aesthetic while still ensuring that they are suitable for use with black text on an Excel worksheet.

Do you need further adjustments to the palette, or would you like suggestions on how to apply these colors effectively in your Excel sheet?