In my case, I don't want to hear anything about what people are up to. I don't want articles, or other such stuff. I don't want to be messaged.
For me, I just want a work history validation mechanism, and a way for legit job offers to appear.
The perfect linkedin for me, would be a way to link to work contacts without ever talking to them. Once linked (eg, when people allow it), I could get contact info if a person has it setup. That is, an email address or similar.
Again, the platform would have zero communication on it, so if you want to talk, then take that email, and email the person!
Outside of that, I want nothing. No communication, news, etc.
I set communication settings to let only people who know me (ie are in my contact list) to contact me (Settings -> Communications -> Who can reach you). The contact list is culled mercilessly once a year (eg. recruiters who specialize in jobs no longer relevant to me are removed). The Email settings in the Communications section are also quite detailed and there are a bunch of preferences you can choose from; I don't get any emails from Linkedin except inmails.
LinkedIn is my only social network (HN doesn't count IMO), and unfortunately I can't get rid of it without impacting my career, so I have incentive to bend it to my requirements. It thankfully isn't too difficult.
HEAR HEAR.
I just want to know about what others are up to professionally.
But how do you curate this in anything resembling an automated fashion? I suppose you might add a box for the requestor to the effect of "how do you know this person" ... but that's way too easy to game
I DO NOT WANT:
Randoms contacting me to add to their network. i.e. people I've never met, nor worked with.
Recruiters spamming me with jobs that I am NOT interested in. Recruiters asking to be added to their network (see previous point).
Invitations to seminars, conferences, etc that have nothing to do with my profession.
"LinkedIn" staff wanting me to sign up and pay for yet another feature that I don't need.
As others have mentioned, no personal updates, humble brags, etc.