I am fortunate to belong to the operating crews of two large N scale layouts. Both are designed for point-to-point operation. One has a double ended staging yard that allows for continuous running if desired. The other is a very long double-track main with large staging loops at each end (actually stacked one above the other). These loops also allow for continuous running if desired. I personally model the Santa Ana & Newport which, when absorbed by the Southern Pacific and connected to the SP mainline, created a prototypical loop of track around central and north Orange County, California. Thus, my HO scale layout offers simultaneous point-to-point AND continuous loop running. The SP ran a mixed train around this loop several times a day to handle local commuters and local express freight. It was labelled the "Merry-Go-Round" train. My layout assumes the SA&N remained independent and operating into the late 1950's. Local SA&N, SP, ATSF and Pacific Electric freight trains have to make their point-to-point runs while dodging the continuously looping SA&N version of the Merry-Go-Round train. This makes for a very busy timetable!
I would recommend designing a track plan for point-to-point operations with some means of connecting the two ends to allow for continuous running when desired. This will give you great operating potential while still allowing you to just watch trains go by. A double ended staging yard would be the best way to make this connection. Use a "through" track down the middle of the yard with "eastbound" tracks on one side of the through track and "westbound" tracks on the other side.
