I did make it through all 12 books, although I was tempted to give up a couple of times in the slower, harder-to-understand books. Reading along with others in the AO forum kept me going, for real. Overall, I am glad I read it and look forward to sharing it with my son in a few years. I am considering adding the sequel, Paradise Regained, to my reading list as well. Challenges are good!
As I was saying (before I went all fan-girl) was that the plot is basic but the way of telling the story is unique. Adam and Eve are created, sin, and are kicked out of the Garden. Before and alongside this story is the fall of the angels and the story of Satan and his demons in hell, trying to figure out how to fight back against God for this punishment. That made it a fascinating read, as I had never imagined creation and mankind from the point of view of the devil before.
Another point of interest was all the mythology included (although this messed with the story's timeline in my head). Milton was masterful in weaving myths and Bible and his own story together to make it almost believable.
Eve was a bit of a doormat at times, but overall I think woman was depicted pretty well, and the beauty of Eve, and the sanctity of marriage was a lovely picture. Adam had his faults as well, but in the end they went out of the Garden together into the wide world.
Finally, there was Jesus. Christ was there from the beginning, and loved man from the get-go. He volunteered (before Man even screwed up, if I remember correctly) to take care of the needed sacrifice. That part was beautiful and had never occurred to me before.