Querying the meaning of the sons of God in Genesis 6

Since the pastor of the church that I fellowship at is scheduled to do a Bible study exploring the Biblical meaning of the "sons of God" or the "bene 'elohim" next week, I am doing my own research. Most pastors that I know shy away from calling the "sons of Gods" extraterrestrials, which I have not been afraid to do even previously on this blog (See previous post where I espouse this view)

After conversation with some church members, reflection and prayers, I have come up with the hard questions that I have emailed to the pastor. Below is the content of my email sent, which I hope the pastor will address:

In prelude to your Bible study on the sons of God in Genesis 6, that I hope to attend, I am sending you my questions in advance. 

I have several questions and hope that you can address them all in your presentation. As such, I am giving you the heads up for you to prayerfully and thoughtfully research and prepare your answers....The questions are as follows:

1. I hear you say that the fallen angel view of Genesis 6 was concocted by the Catholic church. Early church fathers in the 1st century of Christianity, prior to the formation of the Catholic church, such as respected Ante-Nicene father of the early church, Iraeneus espoused a fallen angel view (Schaff p.481). Further, New Testament church leaders such as Peter and Jude cite the book of Enoch, which also espouses the fallen angel view of the sons of God (Jude verse 14-15). Secondly, even if you contend that Ellen G. White espoused the Seth-line view, isn't it possible that Mrs. White was merely espousing the view that she herself was taught and inherited from fallen/apostate  Christianity?
2. Where in Genesis is Seth ever called a son of God? And if there is such a reference in a particular Bible translation, is that context independent of translation?
3.  Doesn't the term "sons of God" refer to only the creatures whom God directly created and not those who came from sexual unions?
4. Doesn't the Hebrew for the daughters of men (בנות אדם‎) actually translate as benot ha-adam? Doesn't the term Adam in this term strengthen the case that they were daughters of Adam?
5. If one is to take the Seth-view, doesn't this view make God seem unjust, writing off the entire generation of Cain from access to his grace and mercy? Doesn't it also seem more just that God would send a flood to wipe off human beings with contaminated fallen angel DNA, than it would be if he wiped off mankind for heterosexual marriages to whomever they desired?

Reference:

Schaff, Philip. ANF01. The Apostolic Fathers with Justin Martyr and Irenaeus: Christian Classics. Grand Rapids, MI: Christian Classics Ethereal Library, 2002. Web. 4 June 2011. <http://www.ccel.org/ccel/schaff/anf01.pdf>