Ability to paste images into MD editor
Images should be pasteable via clipboard ctrl+V as a shortcut, similar to how Github's MD editor works. This would be a gigantic time saver.
Page Approval Function
When a user created or edited a page, it wont publish right away, rather have a admin or higher lever user to approve the modification, then publish.
Move a complete "tree" of pages
Although a wiki is a collection of pages, often they are organised in a tree structure. If you want to move a page that is at the top of a subtree and all pages below it, that is very cumbersome. Adding a "move tree" function would greatly simplify moving, or renaming, subtrees and keep consistency.
Moving a page should update links
Currently when moving or renaming a page, all existing links point to the old page. The correct behaviour would be to update all links to the new page, either optional or explicit.
Sometimes you might have a page that could go under multiple titles. Mediawiki handles this with a thing called "redirects". This kind of feature is espc needed in any large wiki since with multiple editors you can't count on people following the same naming standards.
Templates / Content Transclusion
Have a template or transclusion function, just like in MediaWiki( https://www.mediawiki.org/wiki/Help:Templates ), which would give people the ability to create infoboxes or other types of templates that are used on many other wikis.
Dropdown Navigation Items
Support for child navigation items to allow dropdowns in the main navigation pane. If you have a large wiki, it can be hard to organize your pages without some type of collapsible navigation.
Breadcrumb for subpages
Should (auto) generate breadcrumb links on all the subpages based on the hierarchy of the file.
Is it possible to move entire folders at once? if there's a wiki/documents/diplomas folder and a wiki/paperwork folder, it would be nice to be able to move the entire documents or diplomas folder at once such that you end up with wiki/paperwork/documents/diplomas or wiki/paperwork/diplomas (and now documents doesn't have a "diiplomas" subfolder). Put otherwise, moving a page would move all the sub-pages under it along with it. Especially if it could be done by drag and drop in the navigation view.