What is need most likely is a paging system that doesn't pull down large amounts of data at once. This needs some thinking as it effects the current state of lookup search since it uses what is only on the client and in its model collection.
Search can be rebuilt like it is on the website rendering, where it uses Cloudant / CouchDB full-text search instead (and much better).
Right now, it is possible to insert images into content by formatting the image URL in a certain way. But it would be very helpful and clearer to support it by maybe copying an image embed URL or even auto paste it at the current cursor within the content box.
Because of the way that the collection slug is embed within an document's record, it is hard to rename a collection where the slug needs to be changed too. Each essay that is classified under that collection will need to be visited and the so called collection be selected again as it is considered to be like a new collection with a new slug.
Should either come up with a different way or create a script that goes through the children of a collection to also rename the slugs they are holding of the collection.
Some don't want the published and modified dates at the bottom of every page or even only on certain pages. A global site flag and a page specific flag will be great.
The file upload feature now might be a bit confusing where when you upload a file you must save the record before you can actually use it inside the content. Plus it is not clear that you can double-click on an image to remove it from the attachements of the document, and that with a single-click on an image you are designating that image as the primary one.
Maybe just documenting those facts somewhere around the upload feature is more than enough, but it can surely be clearer.
The content textarea in the fullscreen edit mode is covered by the side nav bar and is not accessible for editing and can't be exited from since the button happens to land underneath that main nav layer. This is most likely a CSS bug on mobile as it does not happen on desktop.
Some like to have comments on their essay pages, so it will be useful to have an option for a site to input a Disqus code that will enable commenting. But also have it support a way to disable it on per essay basis.
Many improvements could be achieved if the admin app was rewritten in AngularJS so less boilerplate code is needed to bind UI with data and such. This will go nicely with the angular-ui module that could provide some useful interfaces to the app.
For those people that have a intermittent connection or just want to work offline, it will be cool to have the admin app support offline editing and such. Being on CouchDB, it is possible to use something like PouchDB to accomplish this.