Here is a color palette that includes a shade that is only slightly darker and brighter than #F8E89D (Very Light Mustard Yellow), along with the previous shades.

json
{
  "palette_name": "Slightly Darker and Brighter Mustard Yellow",
  "colors": [
    {
      "name": "Slightly Darker Mustard Yellow",
      "hex_code": "
                            
                            #F3E09E
                        "
    },
    {
      "name": "Very Light Mustard Yellow",
      "hex_code": "
                            
                            #F8E89D
                        "
    },
    {
      "name": "Bright Light Mustard Yellow",
      "hex_code": "
                            
                            #F2D78B
                        "
    },
    {
      "name": "Medium Mustard Yellow",
      "hex_code": "
                            
                            #FFC107
                        "
    },
    {
      "name": "Dark Mustard Yellow",
      "hex_code": "
                            
                            #B58B00
                        "
    },
    {
      "name": "Deep Mustard Yellow",
      "hex_code": "
                            
                            #A67C00
                        "
    }
  ]
}

The palette now features a slightly darker mustard yellow ( #F3E09E ) that provides a subtle variation while still maintaining the brightness of the original shade.

Would you like to explore more options or perhaps combine these colors in a specific design?