I have only recently come across the Wiki idea in serious use as I delve into the Ruby community, so I can't address some of your issues. But you might want to check out Twiki as well as any other of the many WikiWiki type engines. While mostly geared towards collaboration, TWiki does incorporate some very powerful and interesting RCS functionality (and you can always use authentication to limit who can actually use the edit functions).

Pros: there are a few WikiWiki systems out there written in Perl, and TWiki can use plugins of some sort (so if you need a special feature like a database connection...)-- oh and it's GPL, always a feature I look for in software. Cons: looks like getting the site skinned out and customized could take some time, plus you have to learn the system, but that's a problem with any premade system, no? See UseModWiki for a slightly simpler implementation of the same basic meme.

I think the Wiki method actually does what Everything wants to do, only better (at least as far as the E2 version goes), but doesn't depend on a database backend. I do worry about the security aspects of the systems I've seen, but I think that's mostly me being paranoid and new to the systems. I am planning to implement a TWiki clone on at least one site and probably two others. It seems like it will be easier than trying to roll my own solution.