Disable/hide visual borders when hovered over, atleast in full screen mode. It makes the UI look pretty untidy.
Back in July, we shipped a completely new visual header that lets you disable per visual some or all the various options and doesn't take up space on the page. You can read the details on our blog: https://powerbi.microsoft.com/en-us/blog/power-bi-desktop-july-2018-feature-summary/#visualHeader
