My control line flying of Super tigre G20-15's has been with the same venturi as I would run on the glow version. My tower 40 ran diesel/runs glow on the same venturi. If you open the carb, you will get less suction and thus probably will have to open the needle as you said. Two cycle engines are in one sense just air pumps and the more air you pump, the more power you get. Also the more fuel you will burn.

Jim