Content discovery has already improved thanks to the first attempts at implementing Hive communities (and to some extent tribes as well). One either doesn't know how to look or doesn't have the best intentions not to see that yet.
And all that happens even with minimal interface changes. What will it improve when interfaces go beyond the minimal changes? See Steempeak's beta as an example of a little step forward and you'll understand.
What we really need, and that's a request for a long time, is a well designed #search-functionality. Let's say it's understandable it was postponed till after Hivemind and Hive communities were created and in use.
We have something really powerful on Steem: the possibility to have both communities and tags.
Once we will have well designed search functionalities, the combination of the two can make content discovery so easy.
Let's say we have a "Favorite Movie" community. Maybe we already do, I haven't checked.
And in that community people talk about their favorite movies, obviously.
Let's say you'd like to see an old movie. Wouldn't it be nice to be able to search in the "Favorite Movie" community, for posts with the "#old-movies" tag?
Maybe even contextual autocomplete tags to look for. For example, there may be even more explicit tags, like "old-action-movies" or "old-adventure-movies" or "old-comedy-movies" or "old-love-movies" and so on.
Once you type "o" in the tags field, for the "Favorite Movie" community, several choices are presented to you. By the time you type "old-" the options above are likely suggested.
This brings me to the limitation to one dash for tags on the steemit.com interface. Likely the decision to make this limitation was taken to limit abuse and the number of index keys. Well, since this limitation is only imposed in the tags field (not the in the body field), and other interfaces don't have it, I wonder if it's necessary? You can see above the clear example where more dashes would be useful (true, they can be added via the post body).
Searching should not be a detective work, like in the image above. That's why most won't say search for something online. They will say they'll google for something. Google became synonymous to the online search engine, even if it was a late comer at this party. But everything was stupid simple on their search page.
A well designed search functionality, both #easy-to-use in its basic form, and allowing the #flexibility of advanced search criteria, would put Hive communities and Steem in the position to soar. In my opinion, of course.