Yeah restricting the banner to Green, Red yellow and black trimmed with white fur would be good.
Oh and the Magyars were not Nomads, they had settled pasturial and agricultural settlements. A group of Magyars known as the White Magyars had been living in the Carpathian basin since A.D632, they had an advanced agricultural society by the time the Arppadian or Black Magyars came to EWyrop in the late 800's A.D.