I could be wrong but I think that in showing the forsaken the way he did RJ was trying to show that they had become so self absorbed and selfish, they had committed such terrible acts over so long a period of time that they had in some ways abandoned their humanity.

In effect most of the forsake had almost become a bit like Rand was in TGS. He was obsessed with defeating the DO at any cost that he would do anything/say anything to get that end and he no longer saw people around him as people but just as chest pieces.

Rand was forced into his role and his obsession was far more noble that that of the forsaken but they have gained tunnel vision on gaining power and ruling the world while destroying their enemines. The only exceptions to this seemed to be Lanfear who also loved, in her own way, LTT/Rand and to a lesser extend Asmodean who was seriously lacking in the evil department compared to the other forsaken.