Here is the updated harmonious color palette for Google Spreadsheet, with each color made 30% lighter for enhanced readability while maintaining the overall theme:

json
{
  "palette_name": "Updated Harmonious Color Palette",
  "colors": [
    {
      "name": "Lighter Below Zero",
      "hex_code": "
          
          #B9E3F3
       "
    },
    {
      "name": "Lighter Halloween",
      "hex_code": "
          
          #FF7F50
       "
    },
    {
      "name": "Lighter Fondue",
      "hex_code": "
          
          #FFFEDD
       "
    },
    {
      "name": "Lighter Toxic Frog",
      "hex_code": "
          
          #B0FBC0
       "
    },
    {
      "name": "Lighter Foundation White",
      "hex_code": "
          
          #F1F1FD
       "
    },
    {
      "name": "Lighter Butternut",
      "hex_code": "
          
          #FFBBAE
       "
    },
    {
      "name": "Lighter Candy Floss",
      "hex_code": "
          
          #F6B2E0
       "
    },
    {
      "name": "Lighter Teal Me No Lies",
      "hex_code": "
          
          #6BD6D0
       "
    },
    {
      "name": "Lighter Peach Puff",
      "hex_code": "
          
          #FFE7D6
       "
    },
    {
      "name": "Lighter Pinball",
      "hex_code": "
          
          #E0E0E0
       "
    },
    {
      "name": "Lighter Capri",
      "hex_code": "
          
          #66CFFF
       "
    },
    {
      "name": "Lighter Matt Pink",
      "hex_code": "
          
          #FFCCDB
       "
    }
  ]
}

This updated color palette incorporates lighter shades of the original colors, enhancing readability while maintaining a harmonious feel.

Is there anything else you would like to adjust or add to this palette?