One reason on why the style of Roman temples aren't suitable for Christians is because they're not built like churches, churches have an enormous amount of space and they're made so that people can stay indoors. Whereas, in Roman temples most activities are held outdoors.
I believe it would be Pathos because it relates to emotion.
Logos is based on logic
I don't know what u mean by primary purpose light colors but if you just asking for primary colors these are the only ones.
His friendship with ferdinand david