I don't think passion lacks in LOTR it is just that there is no time.
You can't have a full blown romance in the middle of a war that could possibly destroy everything you hold dear. I think there is quite a bit of passion considering everythin that is going on.
I liked Eowyn because I think her character goes against a man's perception of a woman. (or at least one who is sexist) Although at the time I read the book I was too young to understand the whole sexism thing I have re-read the book (DUH) and sexism never came to my mind.
As has been said before I think Tolkien is in a sense is honoring women through Eowyn. The people who claim Tolkien is sexist probably don't realize that it wouldn't fit in the story if a woman was suddenly almost supenatural and saved the day over and over again. If that happened all those cultures Tolkien made would have made no sense and the characters would have lost their reality.
Middle- earth is basically set in a time where society was dominated by the male. Just this simple often mentioned piece of evidence should therefore make all the accustaions false.
If only people had the brains to see that. sigh...
Now I finally got that off my chest