Adjusting FlattenJson output

[James McMahon]

I have incoming JSON data that begins like this, and that I am trying to
flatten with FlattenJSON v1.16.3:

{
  "meta" : {
    "view" : {
      "id" : "kku6-nxdu",
      "name" : "Demographic Statistics By Zip Code",
      "assetType" : "dataset",
      "attribution" : "Department of Youth and Community Development
(DYCD)",
      "averageRating" : 0,
      "category" : "City Government",
      "createdAt" : 1311775554,
      "description" : "Demographic statistics broken down by zip code",
      "displayType" : "table",
      "downloadCount" : 1017553,
      "hideFromCatalog" : false,
      "hideFromDataJson" : false,
      "indexUpdatedAt" : 1536596131,
      "newBackend" : true,
      "numberOfComments" : 3,
      "oid" : 4208790,
      "provenance" : "official",
      "publicationAppendEnabled" : false,
      "publicationDate" : 1372266760,
      "publicationGroup" : 238846,
      "publicationStage" : "published",
      "rowClass" : "",
      "rowsUpdatedAt" : 1372266747,
      "rowsUpdatedBy" : "uurm-7z6x",
      "tableId" : 942474,
      "totalTimesRated" : 0,
      "viewCount" : 70554,
      "viewLastModified" : 1652135219,
      "viewType" : "tabular",
      "approvals" : [ {
        "reviewedAt" : 1372266760,
        "reviewedAutomatically" : true,
        "state" : "approved",
        "submissionId" : 1064760,
        "submissionObject" : "public_audience_request",
        "submissionOutcome" : "change_audience",
        "submittedAt" : 1372266760,
        "workflowId" : 2285,
        "submissionDetails" : {
          "permissionType" : "READ"
        },
        "submissionOutcomeApplication" : {
          "failureCount" : 0,
          "status" : "success"
        },
        "submitter" : {
          "id" : "5fuc-pqz2",
          "displayName" : "NYC OpenData"
        }
      } ],



* "clientContext" : {        "clientContextVariables" : [ ],
"inheritedVariables" : { }      },*
      "columns" : [ {
        "id" : -1,
        "name" : "sid",
        "dataTypeName" : "meta_data",
        "fieldName" : ":sid",
        "position" : 0,
        "renderTypeName" : "meta_data",
        "format" : { },
        "flags" : [ "hidden" ]
      }, { .....

This is my configuration of my FlattenJson processor:
Separator                                  .
Flatten mode                            normal
Ignore Reserved Characters    false
Return Type                              flatten
Character Set                           UTF-8
Pretty Print JSON                     true

Those lines in red appear in my output like this:
  "meta.view.clientContext.clientContextVariables" : [  ],
  "meta.view.clientContext.inheritedVariables" : {

  },

I don't want to preserve the empty list and empty map. I want to set the
values for these keys to the empty string or null is acceptable.

Can I do this natively through the FlattenJson configuration? If not, what
would be the most efficient means to post-process to what I seek in my flow?

Thanks in advance for any help.