Since at least on the screens page you already know what will be the exact dimensions of the image rendered for each graph, it would greatly improve the rendering if you were to include the dimensions in the <img> -tag .. this would allow the browser to render the layout in correct proportions on the first go without having to wait for all the images to be generated for the page to get the correct layout.

Currently, e.g. when editing a screen, you have to wait for a while for all the graphs to render before you can reliably click on any elements on the screen as it's jumping around all the time with new graphs popping up, same goes for when refreshing a screen.

If you simply render the <img> tag with absolute dimensions specified (with either style="" or width="" and height=""), it will be much smoother.