5. What do you do?
It should be immediately obvious what your company does. If your name, tag line, or logo do not give it away, then the next thing your customers see should tell them (via words or images). Sliders, image grids, and text blocks can help convey what it is your company does, but make sure somewhere on your home page it says what you do. If I cannot figure out what you do, I'm not going to stay and hunt around, I'm going to hit that back button and wonder if you even know what you do.