Hmmm... I'd say Perrin. Too many people call him slow but smart, but I never saw too much evidence that he was unusually smart. HE wasn't dumb... but that's not quite the same thing.
While I still think some of the forsaken, especially the ones gone early, seemed overrated, I have to somewhat agree here.
Until recently with WoT (the last 4 books), I used to skip Perrin's and Egwene's sections on rereads as both annoyed me in different ways, whereas after seeing the full character arc / growth I can live with them better now.
With Perrin, there were often those quotes around being slow but smart, but really he viewed the world more simply than most - many around him would overcomplicate things, whereas Perrin just wouldn't see the complications, and so come up with the simple answer which is also often the best, coming across smart when not necessarily the case, just a different world view.
In the early days, whenever I would read a quote of his around 'people tend to think of me as slow and thus stupid', I would think that this is because he is slow and stupid, given his actions in the early books He got better though