Does anyone else find it interesting that many of Siuan's closest advisers/friends turned out to be Black?

Sheriam, her MoN and one of her close friends since their days as Accepted together.

Delana, also one of her closest friends as well as a woman considered "under her protection".

Verin, a mother figure and late in the game one of the few Siuan trusted with the knowledge of Rand.

Makes you wonder if Delana and Sheriam at least were recruited due to their association with Siuan and the Blacks desire to keep an eye on her and Moiraine.