An important yet often overlooked point in my view is this. Cadsuane says that just 100 years ago there were 20 women of Moiraine's strength in the Tower and 1000 years ago there were more women that exceeded Egwene. The strength decrease of Aes Sedai is linearly correlated to time progression from the Breaking onwards.

So the women who confronted Amalasan 1000 years ago were almost certainly stronger than a random selection of 6 Red Ajah today. And the 6 who confronted Stonebow 2000 years ago were as much stronger again.

So the 6 who confronted Stonebow could well all have been as strong as Moiraine. And we know Rand exceeds all men in strength. Meaning that if Stonebow could face 6 average strength sisters 2000 years ago, Rand might well be able to face 10 average sisters today.