And if you really want to know what are the most important, relevant pages to get links from, forget PageRank. Think search rank. Search for the words you’d like to rank for. See what pages come up tops in Google. Those are the most important and relevant pages you want to seek links from. That’s because Google is explicitly telling you that on the topic you searched for, these are the best.
I like that you said you let PageRank flow freely throughout your site. I think that’s good and I’ve steered many friends and clients to using WordPress for their website for this very reason. With WordPress, it seems obvious that each piece of content has an actual home (perma links) and so it would seem logical that Google and other search engines will figure out that structure pretty easily.
While ordinary users were not that interested in pages' scores, SEOs of a different caliber felt that this was a great opportunity to make a difference for their customers. This obsession of SEOs with PageRank made everyone feel that this ranking signal is more or less the only important one. In spite of the fact that pages with a lower PR score can beat those with a higher score! What did we receive then, as a result?