tl;dr: Let any user add any tag/category to any article, allow each user to up/down vote each tag once (to increase categorization quality), and allow all users to filter HN articles by tag - and tag properties.
Result: When we have only a short time, we see only the types of article that most interest us. When we have more time, we can browse through new or untagged or little tagged articles and apply/vote tags.
Why? Because HN and the HN community are good at curating articles of interest, and I cannot find a better community for suggesting the types of article I'm interested in, but that type is, broadly, off topic.
Longer version, more rationale, details....
I wandered into HN when I was a hackerpreneur - but I'm not anymore.
I stay because of the high quality of articles and comments - but the articles I'm mostly interested in are not about hacking code or hardware or startups, they're about cognition, hacking the mind, pedagogy, etc. Ya know, the off topic stuff.
But the real off topic gems tend to drown in a sea of on topic stuff.
So I spend a fair amount of time filtering through the first four or five pages of stories every day, looking for those non-coding&&non-startup gems that spark my interest. I'd like technology and crowd-sourcing to make this easier for me....
Let anyone add a tag/category to a story, e.g., hardhack, softhack, hardknocks, cognition, mindhack, etc. - AND let everyone vote up/down the tag/category: Voting tags would make them fluid and make the most sensible ones apply to any story.
(The most popular tags, or the most commonly used ones, would populate a dynamic list - this would allow the tag system to grow organically.)
Next, let me filter HN by tag/category, using as many/few as I want. Or none.
I'll start viewing with filters turned on and find recent stories of interest. When there are none (or not enough for this period of distraction), I'll look through recent untagged (or little tagged) stories, and apply tags, or up/down vote tags.
In other words, when I have little time, and need a distraction, I'll find one on topic for me; when I have more time, I'll help manage tagging so that you find one for you, next time you need one.
(Why am I not a hackerpreneur anymore? Well, that's off topic, but tl;dr? My values and interests have changed as I near the big 5-0, I'm not completely enamored of my current gig - IT security consulting - and I've come to realize I don't really want to start or run a business. So I'm irrationally edging back into undergrad studies in a very different field from my original studies... ...but I'm still here because of the very high signal/noise ratio.)