I was trying to suggest that the main source was a street light coming through the window, and the fill was coming from other lamps elsewhere in the house. I shot a wide/two-shot, but I had a hell of a time getting the window to look dark enough to be believable as a street light, and still get some rim on the actors (from the key). The window would blow out, so I stopped down enough to look believable, but the characters lost their edge light as well as detail. I brought in more fill, but that started overpowering everything, almost replacing my key light.
I guess in reality, any lamp you have on inside at night would pretty much either match or be brighter than a streetlamp spilling in from outside. I hoped to use the "street light" as just an accent, and key from some sort of lamp, but the limitations of the location, production design, and blocking all forced me to key from outside the window.
I guess my "fill" could've have been more sourcey and controlled, as opposed to general room ambience. The way I set up the tweenie bouncing into the ceiling, it essentially replicated the overhead pratical that was already in the room, although much dimmer. The pratcial gave me almost a 1:1, which obviously looked horrendous for the tone.