The Avos were not very good fathers to their sons

When you read through the parshas in Sefer berishis, it's hard to escape the conclusion that the Avos did not do a very good job with their sons.

Avraham 

Avraham had 2 sons, while Yitzchak turned out fine, Yishmael did not. Avraham had to kick him out of his house because he was a danger to Yitzchak and he certainly did not follow in his fathers footsteps.

Yitzchak

Yitzchak also had 2 sons (froim the same mother) and again, one went completely off the derech. The Gemara in Bava Basra says the following about what Eisav did on the day that Avraham died. 

Rabbi Johanan said: "That wicked [Esau] committed five sins on that day. He dishonored a betrothed maiden, he committed a murder, he denied God, he denied the resurrection of the dead, and he spurned the birthright." (Baba Batra 16b)

This is not just going off the derech. Chazal describe Eisav as a truly evil person and yet Yitzchak couldn't see it all and in fact, even wanted to bless him. How could such an evil person come from a father like Yitzchak?

Yaakov

While none of Yaakov's sons went off the derech there still was tremendous dysfunction. Yosef's brothers were ready to kill him, and in the end sold him off as a slave expecting to never see him again. 

What can we take from this? On one hand it is refreshingly honest (unlike current hagiographies of Charedi gedolim), on the other hand you can't help but think, these people were not the super giants that Chazal made them out be. They were just like us, they were jealous, they had sex drives, they got angry, they made mistakes, etc.