We are using faq very extensively and it works really great. The answers are all being displayed as html, so you can use links a lot and directly redirect users to the right location. The only difference between Yahoo Help and faq is the fact that you cannot display the questions on one page seperately. But it shouldn't take more than an hour to add this feature (if you really want to add it).
We could copy the /faq/* code to /help/ and call it help. On /help/index.tcl you would see the different module names and could easily click on the one you are seeking help for.
Maybe you could alter the data modell and add a column faq_type varchar(20) or something like that, where you could choose wether the text was a real faq or a help issue. Then you could display only the help issues on /help and the faq issues on /faq.
I think that faq offers everything you need. You could additionally activate general-comments and improve the help step by step. You can add people to the faq group so that not only the site-wide-admin can add a faq-question or alter an faq-answer but every member of that group.