Otimize a consulta de junção de várias tabelas

Tenho tabelas conectadas entre si por chaves estrangeiras (postgresql 13.1).

order: order_id, name
sub_order: mainorder, order_id (foreign key to order), detail
task_group: id, group_name
tasks: id, taskname, task_group_id (foregin key to group_name)
task_kind: id, kind_name
task_task_kind: id, kind_id(fk to task_kind), task_id (fk to task)
time_per_project: person, start_time, stop_time, part, order_id (foreign key to sub_order), 

Espero ter descrito o suficiente. Minha consulta por visualização materializada é a seguinte e funciona muito bem:

SELECT
  so.order_id AS order_id,
  MIN(so.status) AS status_id,
  SUM(AGE(tpp.stop_time, tpp.start_time)) AS total,
  SUM(
    CASE WHEN (tasksgroups.id = 1) THEN
      AGE(tpp.stop_time, tpp.start_time)
    END) AS srut,
  SUM(
    CASE WHEN (tpp.valve_part_id = 1) THEN
      AGE(tpp.stop_time, tpp.start_time)
    END) AS korpus,
  SUM(
    CASE WHEN (tasks_with_kinds.task_kind = 1) THEN
      AGE(tpp.stop_time, tpp.start_time)
    END) AS zwykle,
  SUM(
    CASE WHEN (tasks_with_kinds.task_kind = 6) THEN
      AGE(tpp.stop_time, tpp.start_time)
    END) AS wyprawki
FROM
  intranet.sub_orders so
  LEFT JOIN intranet.time_per_project tpp ON so.mainorder = tpp.project_id
  LEFT JOIN intranet.task_task_kind tasks_with_kinds ON tasks_with_kinds.id = tpp.task
  LEFT JOIN intranet.task tasks ON tasks.id = tasks_with_kinds.task_id
  LEFT JOIN intranet.task_group tasksgroups ON tasksgroups.id = tasks.task_group
GROUP BY
  so.order_id
HAVING (SUM(AGE(tpp.stop_time, tpp.start_time)) > interval '0 minutes');

Quero adicionar outra junção com a tabela da seguinte maneira:

article_group: id, group_name
article_cost: id, group_id (fk to article_group), order_id (fk to sub_orders)

Acabei com o join na subconsulta, pois para alguns projetos contava a mesma linha duas ou mais vezes

SELECT
  so.order_id AS order_id,
  MIN(so.status) AS status_id,
  SUM(AGE(tpp.stop_time, tpp.start_time)) AS total,
  SUM(
    CASE WHEN (tasksgroups.id = 1) THEN
      AGE(tpp.stop_time, tpp.start_time)
    END) AS srut,
  SUM(
    CASE WHEN (tpp.valve_part_id = 1) THEN
      AGE(tpp.stop_time, tpp.start_time)
    END) AS korpus,
  SUM(
    CASE WHEN (tasks_with_kinds.task_kind = 1) THEN
      AGE(tpp.stop_time, tpp.start_time)
    END) AS zwykle,
  SUM(
    CASE WHEN (tasks_with_kinds.task_kind = 6) THEN
      AGE(tpp.stop_time, tpp.start_time)
    END) AS wyprawki,
  ac.transport,
  ac.service
FROM
  intranet.sub_orders so
  LEFT JOIN intranet.time_per_project tpp ON so.mainorder = tpp.project_id
  LEFT JOIN intranet.task_task_kind tasks_with_kinds ON tasks_with_kinds.id = tpp.task
  LEFT JOIN intranet.task tasks ON tasks.id = tasks_with_kinds.task_id
  LEFT JOIN intranet.task_group tasksgroups ON tasksgroups.id = tasks.task_group
  LEFT JOIN (
    SELECT
      soa.order_id AS ordid,
      sum(
        CASE WHEN group_id = 14 THEN
          COST
        END) AS transport,
      sum(
        CASE WHEN group_id = 11 THEN
          COST
        END) AS service
    FROM
      intranet.article_costs
      INNER JOIN intranet.sub_orders soa ON soa.mainorder = project_id
    GROUP BY
      soa.order_id) ac ON ac.ordid = so.order_id
WHERE order_id = 2074
GROUP BY
  so.order_id, ac.transport, ac.service
HAVING (SUM(AGE(tpp.stop_time, tpp.start_time)) > interval '0 minutes' OR ac.transport > 0 or ac.service > 0);

Gostaria de saber se você acha que esta consulta por visualização materializada está ok? Se verdadeiro, é possível obter o mesmo comportamento sem ter uma subconsulta com junção aninhada nela?