If you've spent a few hours on the SteemIT website trying to scavenge quality posts you've probably been frustrated many more times than you've found something worthwhile to upvote or comment on (other than the top posts). With an ever growing user base and incentives, spam will most likely be a commonplace.
Bot vs Manual Curation
Reddit and the likes have reputation (or karma) aswell as bots and human moderators. Skipping past the bot algorithms which will evolve in due time (with things like @Anyx 's Cheetah Anti-Spam bot and @pharesim's upcoming bot that calculates the required sp, watch posts, and enables a whitelist of users that can use tags to add/remove users), manual curation while subjective, is what most non-technical users will be doing to gain SP and SD.
My Typical Day At Work - (Steem)
On a typical work day I sit at my PC for around 8-15 hours a day - mostly using Slack, Reddit, Facebook and reading up on cryptocurrencies in general (and sometimes actual work in between). Those hours are now allocated to curating and producing content on SteemIT.
On a normal day I upvote anything from around 20-40 posts, as I read them in full before upvoting ( Yes, I know most don't but I'm a perfectionist ). The bigger batch of them are actually shared in the postpromotion channel on Slack from well-known users.
The rest are from searching through the vast amounts of posts (mostly spam) on the SteemIT website which is time consuming to say the least, while also making you miss out on quite a few of the gems due to the current filters or non-filters.
Stumbleupon and Why It Matters To Us
StumbleUpon is a discovery engine (a form of web search engine) that finds and recommends web content to its users. Its features allow users to discover and rate Web pages, photos and videos that are personalized to their tastes and interests using peer-sourcing and social-networking principles. - Wikipedia
If I had just one button similar to what Stumbleupon has (see below):
Steps would be relatively simple
1. See first random post
2. Read post
3. If interesting check for plagiarism / If spam flag or skip
4. If unique upvote and/or comment
5. Press button to next post
6. Rinse / Repeat
This option would :
a) Find the hidden gems
b) Combat spam
c) Increase productivity
Final Words
This is more of a proposal which will hopefully be implemented in addition to other proposals like sub-categories and personalized interests. I think 
If you like the post upvote and also any opinions would be gladly heard and commented on.