I completely agree with you, I would love more control over tweet priority.
However, I think part of what makes twitter more unique is that you can't. With reddit and HN, I _only_ see what enough other people have upvoted to a point which intersects how many pages I'm willing to scroll through at a given time.
With twitter though, I find just as much unique (at least to my eyes) content as I do elsewhere. There are a lot of people creating a lot of great content and there are not enough upvotes to bring a sizeable portion of it to the masses. And in the end it primarily comes down to post time, title, and luck. But then with twitter I at least see an article title for a sizeable portion of it.
> but that doesn't necessarily mean you'll like their stream
There is a semi-popular programmer that I care a lot about the project he works on and think he is a tremendous developer. However he sucks at twitter. Consistently. And that's okay, I do too, which I why I so rarely actually tweet myself. But after a few days of following him I had to unfollow him because he tweeted a lot and they were driving me crazy.