Even as an intern I know these things make your site suck. They are things I come across all too frequently and drive me crazy to the point where I want to either delete the site from the existence or go in and fix the issue myself. Unfortunately, most of the time, I cannot do either of those things. What I can do is announce the problems to the world and hope that those responsible listen and do something about it.
First, and this by far is the one that annoys me most, auto play audio.