Barricade is more effective and lasts a long time. It can also be harsh on existing turf roots.
Granular Corn Gluten can be effective short term when applied at 20lbs/k and if weather conditions cooperate, however it can't compare with Barricade for control. Corn Gluten is a great slow release (expensive) fertilizer.
IMHO, liquid corn gluten is more effective than granular if you have the equipment. It's less labor intensive and weather conditions are not as critical.
The cultural methods you are employing; top dressing, proper mowing height, irrigation and seeding will greatly reduce weed pressure.
The nation that destroys its soil destroys itself.
Franklin D. Roosevelt