I used to be able to set width and height for oEmbed media under Settings>Media. I only ever set the width to the same as the content width of my sites/blogs. That way it easily inserted YouTube videos with nothing more than the plain URL. It was perfect. Then this feature was removed. Now YouTube vidoes and other oEmbed content defaults to something narrower than the width of the content section of my sites an blogs. So I'm forced to use a shortcode, making this solution a lot more manual and less-simple than it was intended to be.