There is actually a showwiki.php file included with vBulletin releases for redirection. It just maps showwiki.php to wiki_index.php. For XenForo the file would have to be a bit more complicated than that, and would require db access in order to get going. I will see if we can get something started on that front.
I used to use Link and Downloads Manager, or the decent version of it, a long time ago in 3.5 - 3.6 days. It seemed later ones were by different authors and not quite the same, so when vBulletin developed native albums functionality I ended up moving away from it. Then when I started using wikis on my sites, even before VaultWiki, I just moved all the photos and downloadables we had to the wiki. If I remember correctly, as far as the "Downloads" part of the manager was concerned, it looked and functioned much like XenMediaGallery does (except with a clunkier vB3 feel).
I did not use the "Links" part personally, but to my understanding it functioned like a directory of web sites with preview images, descriptions, and ratings of each one (or much newer versions did that). While a Links directory is something I have felt the need for here (some users wanted to post their wikis and right now we have a sorry-looking thread for that), and building one as a new page-type would be relatively simple, that is not something someone has EVER asked us about doing, and we always agreed there were more important uses of development time, although converting that thread to a nice directory might be a good move in terms of marketing. Perhaps when the current feature request list is down to something like 20 and we need a "fun" one to keep developer morale up.