I have un-followed an interesting source because that person posts so much I seldom see anything else. I wish pump.io had a way so clients could have a category of "semi-follow" where posts do not appear in my stream, but every N posts (ideally N is settable) a post appears that says "xyz has N new posts since Y date. Click here to read that stream."
One alternative, which is basically what I do on Twitter, is to unfollow and assume that anything of real interest will make it to you via other folks' repeats.