I think it's time to redesign [[Special:Preferences]] in MediaWiki core. The tabs are a bit dated and can probably be improved.
I've been thinking about large collapsible buttons stacked on top of each other or doing a sidebar similar to Google Chrome's. Either of these options should be fairly simple to implement. I'll put up some wireframes soon in an [[mw:RFC]] if nobody beats me to it.
https://www.mediawiki.org/wiki/Requests_for_comment/Redesign_user_preferences