Here’s a color palette based on your request for neutrals and a ROYGBIV-inspired cool-muted-deep color scheme.

 <Cool Muted Deep ROYGBIV>
1. Neutral Gray - 
                            
                            #B0B3B8
                         - A soft, balanced gray that serves as a perfect neutral backdrop.
2. Deep Indigo - 
                            
                            #4B2C91
                         - A muted, rich indigo that adds depth and sophistication.
3. Cool Teal - 
                            
                            #007A8E
                         - A calming teal with a cool undertone, offering a serene vibe.
4. Muted Olive - 
                            
                            #4A6E4D
                         - A subdued olive green that provides an earthy touch.
5. Dusty Rose - 
                            
                            #C8A6B8
                         - A soft, muted rose that adds warmth without being overwhelming.
6. Deep Blue - 
                            
                            #003B5C
                         - A deep, rich blue that creates a strong visual anchor.
7. Soft Lavender - 
                            
                            #E2D3E5
                         - A gentle lavender that brings a light, airy quality to the palette.

This color palette combines neutral tones with cool, muted versions of the ROYGBIV spectrum, creating a cohesive and sophisticated look. It balances warmth and coolness, making it versatile for various design applications.

Would you like to explore specific applications for this palette, or do you have any additional requests?