A short free shuttle bus or Uber ride away from Miami airport on NW36 street the Wyndham Garden is a great location for spotting, and well complimented by the Pilot House bar and restaurant on the 6th floor with an exceptional views and good food (both indoors and an outside terrace).
Hotel: Rooms ending *02 through to *09 have views looking toward the west, and are best. Rooms ending *10 through *20 look east and are not as good. If you are looking west you'll see movements on the two parallel runways closest to the hotel (northern runways) You'll also see arrivals or departures on the southern runway and cross runway if they are arriving or departing to or from the west. Due to angles you won't see arrivals or departures on those runways to or from the east, however at the end of the corridor there is big window that allows you to see these. The 9th floor (top) does not have this end of corridor window, therefore room 802 is better than 902. This visit I had room 902 and just nipped downstairs for the occasional movement I would not see.
Pilot House: This is the restaurant/bar on the 6th floor. It has an indoor area and an outside terrace. You'll see all movements from up here. The food is very good too. Please note the Pilot House is also open to non guests and is a great place to relax for a few hours. https://www.thepilothouse.us/
Above: views from the Pilot House restaurant on the 6th floor.
Above: view from room 802.
Above: view from the end of the corridor on the 8th floor.
Above: Inside the Pilot House.
Above: Outside the hotel.