One problem I see with this is that it could be used to turn hubski into a hivemind-like place for you. I personally come to this site to see different insights and opinions; most people would abuse this feature by "starring" those people whom they agree with.
..just like they would 'ignore' the people they don't agree with. My Hubski is diverse, and I follow most major players in the community as well as casual, on-and-off users. That's how I like it. fcg here may not, and if he wants to stay in a cozy bubble of a couple common interests, that's okay by me cause it doesnt hurt me in any way; we're all hubskiing with individual perspectives and contributing differently here, so we couldn't hivemind this place even if we tried. In other words, each of us is that guy who lived with a pack of wild bears and filmed it. We can set up camp and chill with everyone, catch some fish and watch how things go down. But once you get cocky and forget this isn't your land, you'll be a cold little hill of grizzly turd before you knew what hit ya.
I do want to avoid the bubble that my last aggregator ended up putting me in, but agree with you that it should really be up to the individual user. Perhaps highlighting the posts my "starred" friends post in my feed, without changing the order would solve this. It would prevent my feed from being dominated by just a few users, but would still allow me to easily pick out the content shared by people I already know and trust the opinions of.