Twitter has a very good signal to noise ratio for me so far, even with images, videos and promotion tweets (which are all detrimental to quality).
Part of that success is the ease with which I can follow/unfollow people. It is often the second point of contact to people I met somewhere, e.g. conferences or other social gatherings.
That said I have just uninstalled the mobile app, because I got an e-mail promoting private messaging (why?) and get the overall feeling, that I am no longer the target demographic for Twitter (tech savvy power users that tweet themselves vs. mostly consuming VIP followers?!) since Twitter does much to worsen my experience (aforementioned imgs, videos, muting, etc.).
