The several notes and memos help with the lore
They have a lot more depth.
Strategies and stuff.
On a related note, what about certain missions like the rescue camp(compile it into one page?), gauntlet and other unique ones?
And finally, should ALL missions get it? Y/N?
You raise a good point --- that each Shadow Lair might have enough content to merit its own wiki page --- but it's hard to judge that until we see the content. Also, there is a danger of ending up with many tiny articles that no one edits. My advice is to write the detailed text you want at the Shadow Lair article. Once that article gets too big, we can split it into smaller articles.
Basically, writing the content is the hard part, while splitting it into articles is the easy part. Do the hard part first.