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My first rule is no audio or video that auto-plays. I just hate that personally, and I think it drives a percentage of your traffic away. That percentage is probably small, but there I doubt there is anyone who decides to stay on the site because of it, so there is nothing positive that comes of it.
I would say the same about pop-ups. A significant percentage of visitors will have a pop-up blocker, so you can't count on whatever message you want to convey actually reaching anyone. Many more people will just close them immediately. A waste of time and a distraction, in my opinion.
For the most part a clean, visually appealing design is what I prefer, with simple UI to allow visitors to navigate the site. I try to avoid the wall of text if I can help it, but sometimes companies want that on their landing page. Of course, whoever is paying gets to make the ultimate decision, but I think of the landing page as the cover of a magazine, and you don't usually see articles on the cover.