Something I'd like to see in PHP is a little more in the See Also section. They're pretty good, but it's not quite as spider-web like as I'd like. For example, yesterday I added a few links from md5() and sha1() to hash(). Lot of people know about md5() and sha1() within PHP, but I find hash() is rather unknown overall, which is a pity as it exposes a tone of different hashing algorithms.
If there's any pages you think should be linked, let me know in a comment or email and I'll add it to the sources. Better yet, join the doc team and cut me out of the process
The astute amongst you might notice that there isn't a link to the appropriate functions even if you refresh now, check out the docs