I've read all 3 books. And if you've 'read WoT several times', but not managed to see the similarities, I begin to wonder...I too have read WoT several times and see absolutely no relationship between the two series. I wonder if you have really read Brent Weeks.
Let me point out a few.
Seal Folk and Sethi: Sea folk mark their families and rank via medallions/chains running across their cheeks. As do Sethi. Both seafaring races, both are comfortable going topless.
Children of the Light and the Lae'Knaught: Both hate channelers/mages/magae (whatever), both have no real homeland-therefore are independant armies answerable only to themselves. Same symbol is used by the pairing, as is their nickname (children) and what they say they fight for (the light).
The Chantry: Member's called 'sisters', describe the casting/making of spells as 'weaving', home is on an island.
The White tower: Members are sisters, weave spells, home-an island...
Ow, and Sister Ariel? Reeks of Verin Sedai.
Rand Al Thor: Dragon tattoos on his arms.
Logan. Dragon tattoo on his arm,
Swordforms by both authors as good as identically decribed.
Bonding: Both series have it. Both use them in much the same way. Both have forms of compulsion (look at Logain's bonding of the sisters sent to destroy the Black Tower) as well as the ability to sense both the partners direction and distance as well as their condition.
Curoch and Callandor: Focuses increasing the amount of power wieldable.