(anon for shyness, nothing more) In the "list of pages I would love to see": a list of the 501st members (pre order-66 is my personal interest), when they joined, died. Not details, just, who's who in the 501st. Because it's it's the kind of detail that's hard to easily gather. And some of it is totally contradictory -- Legends vs canon -- but even knowing the contradictions helps.
Sort of like the list of Jedi who survived the Purge? Once you know a clone's name, looking up info becomes easy. But knowing who was in the 501st -- or like, other legions! -- is really hard to pull from wookiepedia because the "list" doesn't exist in one place.
Anyway, that would help a humongous lot for fic writing, and it's not something Wookiepedia does well (or at all): lists of background characters, and their timeline entrances and exits from the GAR.
It will probably take a very long time for us to do this because it's just... so enormous, but luckily other people have done it! We can't 100% vouch for the accuracy, but two heroes have resources that you might be interested in: a spreadsheet by @clonetroops and this post by @propheticfire.
You can find more handy links to clone wars references here!