[ArathornJax]

Indeed I think that Tolkien's experiences in war provided for him a depth that he was able to use with his characters, including Merry and Pippin. An interesting view is too look at how the experiences of each of the Hobbits in terms of how the deal with the after affects of war is similar yet different.

As for he Nazgul, I think their smelling of blood was a catch 22 for them. First, it reminded them of what they were orginally, human and mortal, and for that,they desired blood because they wanted or desired to be human or at least mortal again with all their power and glory back. I think they desire it most of all because they wanted their individual freedom or independance back.
Yet they also hated the smell of blood because it reminded them of what they had given up to obtain the power, wealth and control that they had had while mere mortals. Imagine obtaining everything that the world says you should want, power, wealth, dominion, strength and glory, and then becoming a mere servant to the one who gave it to you. Living in servititude and living between life and death. I also think they hated it because they had rejected this life and had become purly in the control of Sauron. That would gall someone who in the past had been a formidable leader, even one of the key leaders of their day and they eventually fell, one by one under the dominion and control of Sauron. Imagine Ar-Pharazon as the Witch-King. There would have been some desire to have that power back independant of Sauron, and also hatred that he was in servititude to Sauron. Not sure I am making sense as it is late so I'll stop and retire.

Cheers!