I have noticed that very many people use runway 12/30 for landings and 12 for departures, 1L/19R for arrivals and departures. I would like to make a request for all IFATC who choose to be that ATC at KIAD.
No intersection departures unless on runway 30.
There are never runway 12 departures, and it is very rare that aircraft land on 30 and 12.
There are zero arrivals/departures on runway 1L/19R.
Runway 30 is used for most departures, except for UAL Express, and various international airlines (except for Korean Air, SAS, and Emirates).
Runway 1C/19C is used for heavy and international arrivals.
Aircraft going to the Middle East and India depart from 1R/19L.
1R/19L is used for most United Airlines departures.