Draw needs a full-fledged layer management tool, comparable to that found in other vector graphics editors. The layer list can be shown and hidden with an arrow next to the page handle. Just like with pages, clicking a layer handle gives you a toolbar for that layer.
LibreOffice needs a pop-up color picker (a quick pop-up, not a dialog) that would allow the user to choose any color in a variety of ways (from a pallete, RGB, HSL, CMYK, etc.) and would integrate an eye dropper.