SQL - BigQuery - Optimized Query

SELECT
  MIN(start_station_name) AS start_station_name,
  MIN(end_station_name) AS end_station_name,
  APPROX_QUANTILES(tripduration, 10)[OFFSET (5)] AS typical_duration,
  COUNT(tripduration) AS num_trips
FROM
  `bigquery-public-data.new_york_citibike.citibike_trips`
WHERE
  start_station_id != end_station_id
GROUP BY
  start_station_id,
  end_station_id
ORDER BY
  num_trips DESC
LIMIT
  10

WITH
  trip_distance AS (
SELECT
  bikeid,
  ST_Distance(ST_GeogPoint(s.longitude, s.latitude),
   			  ST_GeogPoint(e.longitude, e.latitude)) AS distance
FROM
  `bigquery-public-data.new_york_citibike.citibike_trips`,
  `bigquery-public-data.new_york_citibike.citibike_stations` as s,
  `bigquery-public-data.new_york_citibike.citibike_stations` as e
WHERE
  start_station_name  = s.name
  AND end_station_name  = e.name)
SELECT
  bikeid,
  SUM(distance)/1000 AS total_distance
FROM
  trip_distance
GROUP BY
  bikeid
ORDER BY
  total_distance DESC
LIMIT
  5

SELECT
  wx.date,
  wx.value/10.0 AS prcp
FROM
  `bigquery-public-data.ghcn_d.ghcnd_2015` AS wx
WHERE
  id = 'USW00094728'
  AND qflag IS NULL
  AND element = 'PRCP'
ORDER BY
  wx.date

WITH bicycle_rentals AS (
  SELECT
    COUNT(starttime) as num_trips,
    EXTRACT(DATE from starttime) as trip_date
  FROM `bigquery-public-data.new_york_citibike.citibike_trips`
  GROUP BY trip_date
),

rainy_days AS
(
SELECT
  date,
  (MAX(prcp) > 5) AS rainy
FROM (
  SELECT
    wx.date AS date,
    IF (wx.element = 'PRCP', wx.value/10, NULL) AS prcp
  FROM
    `bigquery-public-data.ghcn_d.ghcnd_2015` AS wx
  WHERE
    wx.id = 'USW00094728'
)
GROUP BY
  date
)

SELECT
  ROUND(AVG(bk.num_trips)) AS num_trips,
  wx.rainy
FROM bicycle_rentals AS bk
JOIN rainy_days AS wx
ON wx.date = bk.trip_date
GROUP BY wx.rainy