[The Saucepan Man]

Reading through this thread, it did occur to me how "idealised" most of the female characters in JRRT's works are. They are all portrayed as attractive - indeed many are described as being exceptionally beautiful. Very few male characters (Elves apart) are described in these terms. Indeed, we are first introduced to one of the central male characters in LotR as "a strange-looking, weather-beaten man". And Frodo chooses to trust him because he thinks that a servant of the enemy would "seem fairer and feel fouler".

Also, there are no evil Human/Elvish/Hobbit female characters (ie excluding Shelob and Ungoliant). In fact, there are no female characters with flaws that might cause us to disapprove of them in some way. In other words, there are no female Feanors, Wormtongues or Maeglins. The only female character that I can think of that comes anywhere near is Lobelia Sackville-Baggins, and her flaws are petty in the scheme of things, and she ends up with our sympathy. Eowyn's disobedience to Theoden has been described as a "flaw", but it is one that the reader can thoroughly approve of.

Having said that, the world of LotR (ME at the End of the Third Age) is a male-dominated one. The powerful female figures in JRRT's works are (almost without exception) Elves or Maiar. And the only truly powerful female figure in LotR is Galadriel. She hardly seems a likely recruit for the Fellowship - she is far more believable as the ruler of a realm where the Fellowship are able to find rest, and as the provider of guidance and gifts. (She does have a more active role - the defence of Lothlorien against Sauron's forces and the destruction of Dol Guldur - but this takes place "off-screen").

It seems to me that the only female character who might have "fitted in" to the Fellowship is Eowyn. She is the most down to earth - the one that the reader can most identify with. Consequently, she is the most believable to the human reader, certainly the most "well-rounded". But, as others have said, it would have been unbelievable, in the context of the world of LotR, to introduce a character like her into the Fellowship. She works best as a character who, in this male-dominated world, is only able to involve herself in the action by means of an act of deception.