Great work already... Though threads themselves don't always follow the date name, but I figured the content is at least traceable to of that time period.
Yes, I've put threads in the forum the article/content belongs to. Like if a thread was started in 2004 but discussed an article published in 2002, then it will be in 2002. I think this will help seeing how the discussion surrounding asexuality has changed with time in an easier way.
Though not much can be said, an alphabetical order for archived threads with pinning the actual index, may make finding content easier. Supplementing that could also mean renaming threads to better reflect the content for better alpha/numerical order, of course... This is subject to a lot of work and technical limitations...
I would never rename threads, as that would damage our members' and site's history. I am not sure how to add an alphabetic system: should we go with newspaper's name, title of the article, authour of the book, title of the book or else? I made it chronological to show how things have been changing.
I have also not put the name of threads in the index, but the name of the content (article, book or else). This is because for example a thread named "OMG OMG OMG" or "I've found this" is not really helpful. Using the search function on the index to look for something specific should give the best results this way, hopefully.
It looks OK as it is, a good chronological order of things can easily spark interest for future historians/researchers.