Hey there.
I love MediaWiki and have been using it everywhere for years. Recently I've been doing some rather major documentation and I realised there were three features which would be really handy for me (if these or similar already exist I would love to know!):
1. For links to articles in sections on the same page it would be really handy if we had syntax like: [[#unity|]] which would auto-complete to [[#unity|unity]] for you.
2. For duplicated content it would be handy if you could define a bunch of "variables" down the bottom of a page and then reference them from elsewhere. I am aware of templates, but those are overkill and difficult to maintain per my use case (my use case is documenting the "purpose" of a computer, I duplicate this in various places, but don't want to maintain templates for that).
3. It would be cool if for any given wiki page an "estimated reading time" could be provided. Along with maybe a word count, character count, etc.
Since I'm here, quick thanks to the MediaWiki community for creating such wonderful wiki software!
Regards, John Elliot V