Please make user be able to comment in documentation page to explain that is not explained in the doc or inform the reader about error in documentation, so an error in doc can already be noticed before it is fixed, as the doc seems use static file, it can use disqus or fb comment if have some reasons cant implement his own Javascript comment form for it.
I think YII now is in a stage that enriching its documentation is much more crucial than adding features.
YII nowadays is feature-rich. but the documentation hasn’t been matured as the YII project itself grew up.
There is a big lack of working examples and newbies usually have problems starting up, user contributed notes can firmly fill this gap.
Looking at the PHP documentation, with its user contributed notes and plenty of working examples, it usually address most user ambiguities and issues without any pain. I believe that the number one reason the PHP have became so widely accepted, is the strong documentation.