While searching for pictures of Mitchel Field I came across several pictures of Selfridge Field in Michigan, and was struck by the similarities in their design. This should come as no surprise as they were both updated and built at about the same time, probably with similar master plans and building designs. The hangar Line , Operations building, Base Hospital, and Firehouse are virtually identical, and other buildings are remarkably similar. I then discovered the Historic Preservation Application which confirmed my thoughts.
"The Army Air Corps Base (Mitchel Field) was designed and engineered by the Army Corps of Engineers and built by the Ralph Jannotto Construction Company, a local Long Island contractor. Much of the field’s construction was also assisted by workers funded through the Works Progress Administration (WPA). Mitchel Field was built on a national standardized design established by the Office of the Quartermaster General demarcating building types, building locations, and general street and landscape plans, making it similar in concept to other Army Air Corps fields built around the country at the same time. As a result, historic aerial photographs of Mitchel Field look similar to historic images of Selfridge Field in Michigan (extant), March Field in California (extant) or Hickham Field in Hawaii (extant, NR Listed 1985). While these bases were built to serve the young military technology of aviation, they were laid out in a traditional military plan featuring two grand perpendicular axes intersecting at a large parade ground."
"The architects of the Army Quartermaster Corps established standardized designs for base construction during the early 1930s; Mitchel Field’s buildings were designed based on these models. These standard plans designed for the Army Housing Program, hangars, office buildings, and other miscellaneous structures were embellished in each region to reflect that area’s particular history, architectural styles, and local building materials. Posts on the Atlantic Seaboard, for example, typically featured buildings designed in the Quartermaster's version of the Georgian Colonial style ........ Excepting functional buildings like the hangars and warehouses, Mitchel Field’s buildings were entirely designed in the Colonial Revival style. The Colonial Revival ........, was commonly used for government buildings during the 1920s and 1930s. In addition to often meeting functional needs, the style was symbolically satisfying. The Colonial Revival represented a national identity and also reflected nostalgia for a simpler period in the country’s history that may have been especially appropriate in contrast to the rapid innovations associated with flight." 
In 1935, Selfridge Field became part of the top-level General Headquarters (GHO), Air Force, along with five other strategically located installations: Mitchel Field in New York, Langley Field in Virginia, Barksdale Field in Louisiana, March Field in California and Hamilton Field in California. A large expansion program was launched in 1939 to train four new pursuit groups at Selfridge for eventual assignment to other GHQ fields. Many of the temporary frame buildings still in use today were built at that time, when a $13.5 million construction program was started at Selfridge.
Here are the photos side by side for you to enjoy too! Mitchel on the left and Selfridge on the right.
Most views found across the internet. Thanks to all the anonymous contributors.
 Gary Monti (edited by Jennifer Betsworth, NY SHPO) Cradle of Aviation Museum
United States Department of the Interior National Park Service / National Register of Historic Places Registration Form, February 2018