Of course, I'm sure this stuff gets sorted out by the time Steemit heads out of beta. The best thing about it is the platform is open. I'm sure someone's building an app right now which does what you describe - screen out useless content.
But I can't wait! Maybe it's just me, but I find my Steemit experience incredibly annoying with useless posts. So, I'm muting whatever I can, and I thought maybe such a list would help other steemers too.