Wiki
The wiki formatting is arcane and highly limited, with zero documentation and very little capacity or flexibility. Has simply loading up with MediaWiki been considered? MediaWiki is free, easy to install, has massive community support, is very well documented, and is updated frequently to modern standards.
It would be pretty trivial to write a plugin for it that preserves ALL existing wiki content, with automatic templates that replicate all of the extant tags for backwards compatibility. Much more powerful editing, versioning, formatting, and user priv control would go a LONG way towards sensibly organizing games and reducing the need to micromanage and kludge together pages by GMs.
I highly HIGHLY recommend using MediaWiki instead of the existing homebrew. Please.