Preference to set Quick Preview default to "Original size" and other things
Current, it defaults to "Fit to screen" and it's rather redundant because I can already see a thumbnail of it – i.e. 99% of the time when I do a Quick Preview, I don't want to look at a tiny version of the design again; I want to see it in full size.
Related to this is to dynamically use as much of the available screen space as possible for the Quick Preview window. I have a 27" monitor and there's no reason why it arbitrarily sets the max width to only 1,275px, leaving roughly 640px of unused screen space on either side (meaning roughly 50% of the width is unused).
Also, what would be very helpful is to allow click-drag in the Quick Preview window so it's easier to scroll a large design.