System does not have enough vents to properly heat and cool home. Want to add mini-ducts to existing duct work-without adding the high velocity air handler. Two story town-home about 1300 square feet. New heating system was installed in 2007. Purchased home in 2008 and added air-conditioning + whole home air purifier to central air system. I am told by the company that installed the air conditioning that the existing furnace and blower are more than powerful enough for the size of our home. Vaulted ceiling in the living room with only one vent, which is at the end of the duct work. Main supply duct has one register immediately above the unit with a register about 6 inches off of the main duct(which blows out an insane amount of air). It then continues up into the attic space and has 3 branches off of it, bathroom, guest bedroom and master bedroom- in that order, finally reaches living room vent. So largest room in house gets the least amount of air. Guest bedroom seems to get more air than master bedroom. Want to add more vents to system by adding mini ducts(to reduce the amount of remodeling work needed), but do not want to purchase the air handler for the system just the mini ducts. Was hoping to remove the main kitchen vent and install mini vents off of a branched 7 inch duct into the kitchen. Is this possible or do the mini ducts only function properly when used with the high velocity air handler?