We had our basement system inspected and tuned-up last Tuesday. The system is a 2003 Trane XR11 1.5 ton heat pump that heats and cools the finished 2200 sq ft basement. I questioned the tech about if a return should be added to the system to help the game room feel more comfortable in the winter. He was able to increase airflow to the system. The current supply serving the room is a 6 inch. He said that a 6 inch return could be added but he also said that it was not really needed and it will have to go in the ceiling. There are currently 2 other returns (One is a 12 inch in the theater room where the thermostat is located and the other is a 6 inch located in the man cave (billiards room). Both of those returns are located on the lower section of the wall. There's a total of 6 supplies in the basement: an 8 inch in the theater room, a 6 inch in the man cave, a 6 inch in the music room, a 6 inch in the workshop, a 4 inch in the unfinished bathroom (which will be finished starting this spring) and of course the 6 inch in the game room. The workshop and music room supplies are coming off an 8 inch trunk. All of the supplies are located in the ceiling.

My question is, is he right that a return will not be needed? Are the current 2 returns enough for the system?
Thanks in advanced.