oddjob,
The "kilts" are long tunics, not kilts. They also wore a form of tight fitting trousers called Braccae. These reached to just below the knee and were linen in warmer climates and wool in the more northern areas. (Germany, Britain etc.)
Red and white/off white are the two most common and evidenced colors of tunics used by the Romans. There is some manuscript evidence of a yellow tunics when describing Roman cavlary and blue or grey when describing sailors. But the evidence is so sparse as to not give this the "one and only" reference. These could both be a description by one person from one source and should not be considered as gospel or s.o.p.
As for your advesarial troops, that depends on whom and when, they are fighting. Goths?, Gauls? Picts? Thracians? Celts? Saxons? Jutes? etc.
Mike
"Imagination is the dye that colors our lives"
Marcus Aurellius
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