Please add to this list!
There's no need for lenghty articles on any of these characters - there are plenty of sites that do that, and -what's better- of course we all have our tattered, dog-eared copies of the master's work within reach.
The main point of the character pages is their 'What links here' page (see the toolbox; bottom left of your screen). Every time you put a character's name in double square brackets on a chapter page, a link to that chapter will appear on the 'What links here' page of that character, thus creating an index of chapters in which this character plays a role. So there really isn't much point in creating a character page for a character that (as of yet) has no role in the interactive story.
This also goes for the locations page.
(NB: To create a meaningful index, please only link to characters if they indeed play a role. Example: in the first chapter Boromir is mentioned in the last line, but he's not actually there, nor is this a flashback in which he has a significant role.
The reverse also applies: because Faramir appears in every single chapter, there isn't much use in linking to his character page from every single chapter for all this would create is a list of all chapters.)