Mapping reccomendations

[ansamHox]

I am using 7.3 to display transactions in my mobile app. When user logs in, it shows last 5 transactions. If he clicks on "transaction history" (opens new page with the same list but with filter in header and load more button in footer) then user is able to perform search/filter operations (select date, amount range or find via description and name field). My approach is to set all fields to "index": false except one new field "query_field" which is copy field of "name" and "description" so users can search on them. Is this ok approach, and can I put "description" field as "keyword" but store it in copy field as text. I want just faster performances on app loading.

PUT _template/history_tx
{
  "index_patterns": [
    "transactions*"
  ],
  "settings": {
    "index": {
      "number_of_shards": "3",
      "number_of_replicas": "2",
      "sort.field": [
        "account_id",
        "date",
        "order_id"
      ],
      "sort.order": [
        "desc",
        "desc",
        "desc"
      ]
    }
  },
  "mappings": {
    "_routing": {
      "required": true
    },
    "properties": {
      "@timestamp": {
        "type": "date",
        "format": "strict_date_optional_time||epoch_millis",
        "doc_values": false,
        "index": false
      },
      "query_field": {
        "type": "text"
      },
      "order_id": {
        "type": "keyword",
        "index": false
      },
      "date": {
        "type": "date",
        "format": "strict_year_month_day"
      },
      "initiator": {
        "type": "double",
        "index": false
      },
      "amount_before": {
        "type": "double",
        "index": false
      },
      "message": {
        "type": "keyword",
        "index": false
      },
      "account_id": {
        "type": "keyword",
        "index": false
      },
      "description": {
        "type": "text",
        "index": false,
        "copy_to": "query_field"
      },
      "order_type_id": {
        "type": "long",
        "index": false
      },
      "v_pnb": {
        "type": "keyword",
        "index": false,
        "doc_values": false
      },
      "currency_id": {
        "type": "keyword"
      },
      "vd_amount": {
        "type": "double",
        "index": false,
        "doc_values": false
      },
      "name": {
        "type": "text",
        "index": false,
        "copy_to": "query_field"
      }
    }
  }
}

• Sorting by user_id, date and order_id because I want to always show latest transactions for particular user.

• query_field is text and combination of name and description because I want users to query something like "Phone bill" or "John Doe". Can I set name and description as keyword and then save them to text in query_field?

• order_id is "index": false, but I sort index by order_id, is that even possible?