There need to be more strict settings for autoplay, not only for video and audio, but for huge GIF files too. I'd put them under "energy saving" settings, as reduced network activity would benefit for server too, not to mention all CPU cycles saved for not decoding all media on client side. Autoplay activation triggers should be reviewed as well, as some sites will happily start autoplaying all media after scrolling down using main scrollbar. That's probably only me, but I still consider scrollbar a part of browsers chrome, not part of website. So interacting with it should not give any hints to website, at least where media autoplay is concerned.