I'd love to see the option of video safe margins within VS.
Out of interest what for? Unless you work in broadcast there's not point in these limits these days.
Personally, I use them to make sure I don't let any elements of the video stray too far from the middle of the frame. As the video is white with the surrounding edge as white, I worry that because of this margin the program gives me around the video I may place something important where I think looks good within VS but once exported it appears much more to one side than I had planned. Sure I could use the guides within VS, but they move with the canvas and I would prefer a quick on/off switch for some margins such as these.