Let’s go with a nature-inspired color palette that is both visually pleasing and distinct for your 20 individuals. Here’s a suitable color palette:

 <Nature's Palette>
1. Forest Green - 
                            
                            #228B22
                         - A deep, rich green reminiscent of lush forests.
2. Sky Blue - 
                            
                            #87CEEB
                         - A soft, clear blue that evokes a calm sky.
3. Sunflower Yellow - 
                            
                            #FFD700
                         - A bright and cheerful yellow that brings warmth.
4. Coral Pink - 
                            
                            #FF6F61
                         - A vibrant and lively pink that stands out beautifully.
5. Earth Brown - 
                            
                            #8B4513
                         - A grounding brown that represents the earth.
6. Ocean Teal - 
                            
                            #008080
                         - A soothing teal that reflects the tranquility of the ocean.
7. Lavender Purple - 
                            
                            #E6E6FA
                         - A soft, light purple that adds a gentle touch.
8. Peach Orange - 
                            
                            #FFCC99
                         - A warm peach that adds a friendly warmth.
9. Mint Green - 
                            
                            #98FB98
                         - A refreshing light green that feels cool and revitalizing.
10. Slate Grey - 
                            
                            #708090
                         - A neutral grey that can balance out brighter colors.
11. Raspberry Red - 
                            
                            #C72C41
                         - A bold red that adds energy and excitement.
12. Goldenrod - 
                            
                            #DAA520
                         - A rich golden color that is both warm and inviting.
13. Cobalt Blue - 
                            
                            #0047AB
                         - A strong blue that is vibrant and deep.
14. Periwinkle - 
                            
                            #CCCCFF
                         - A light blue-purple that is soft and whimsical.
15. Burnt Orange - 
                            
                            #CC5500
                         - A warm, earthy orange that feels autumnal.
16. Cream - 
                            
                            #FFFDD0
                         - A soft, neutral cream that adds warmth without overpowering.
17. Seafoam Green - 
                            
                            #2E8B57
                         - A calming green that resembles sea foam.
18. Blush Pink - 
                            
                            #FFC0CB
                         - A soft, gentle pink that adds a touch of elegance.
19. Charcoal - 
                            
                            #36454F
                         - A dark, muted grey that can complement brighter colors.
20. Burgundy - 
                            
                            #800020
                         - A deep, rich red that conveys sophistication.

This palette is inspired by nature, providing a harmonious blend of colors that are distinct yet aesthetically pleasing. Each color has been chosen to ensure that individuals can be easily identified by their unique shade without clashing with others.

Would you like to see any adjustments to the palette? Or do you have any specific colors in mind that you would like to incorporate?