The single most important feature would be more options for displaying images. Right now EF can only display a list of items in a library. Some sort of card view would be necessary, preferably with lots of options for customisation.
Take a look at the (interestingly named) Eagle: https://eagle.cool
I use Raindrop (http://raindrop.io) for bookmarks, organising images, and as a read later service. All the rest goes to EF. I would love to be able to do everything in one app, but so far I haven’t found one that does it all.