After Krishna, who are the top 10 most intelligent characters in the Mahabharata?

There is a very thin line of difference between intelligence and idiocy

Intelligence as a filter or parameter is very subjective and leaves a lot of scope for challenges and opinion. I have rated the following people based on knowledge and capacity to create an impact by their knowledge

1 - Shakuni
The only mastermind, the grand master on the kurava side who was capable of strategising and drawing parallel plans to nullify the pandava moves and negate  enemies

2 - Draupadi
This unforgettable heroine is way smarter than any of her husbands or others in the court of yudistra, SHe possessed great intelligence and was the force and ghostwriter behind all of his decissions, a lady with great spirit, valour and virtue. Her story is a saga of suffering and disgrace but she took everything in her stride and vanquished each one of the perpetrators of her humiliation and agony

3 - Sahadeva 
Sahadeva is intelligent but not cunning, he also is said to have a gift of prediction and foresight. Unfortunately always overshadowed by the might and skills of rest of his brothers 

4 - Vidhur
the most capable administrator, he is the real decision maker and control center of hastinapur considering the unignorable limitation of the rulers. While the rest of the royals were busy resolving personal conflicts and desires, the growth of the empire was dependent on the able shoulder of vidhur

5 - Satyawati
The capacity to have managed and run the empire post loss of husband and sons justifies her inclusion and position in the list, One cannot ignore the fact that she was always backed by Bheeshma,but to run the country in that era requires skill and capability

6 - Drona
the teacher of PANDAWA and KAURAWA. They were prepared to be the skilled KSATRIA - warriors, ready to dedicate their life for the fatherland. As a result of good and serious teaching, they were very skillful to use almost every kind of weapons

7 - Bheesma
FOr obvious reasons, he would have featured was above but his reckless and stupid decissions based on his interpretation of what his "dharma" was makes him apprear so low in my list

8 - Yudhistra
A just and intelligent ruler, the kingdom flourished during his era post war

9 - Karna
The just and principled warrior who charmed everyone with his ability and intelligence. He infact is the true unsung hero.

10 - Too many people who were smart in their own respective jonre like Kripa, Aswathhama, Parakshit, Duryodhana,Kunti