I am not sure if I could say Gan is good, but I would agree she/he/it is Maybe of the white. But only if you consider the 'current' reality the Tower holds together the white. When the Prim receeded the duality of light/dark white/red began. Maybe Roland will introduce a third element in the balance of the Tower if he ever breaks the loop. I don't think Gan cares one way or the other - as long as the balance is held. But I will have to read the Graphic Novels to see if there is more information to change my perception.