It would be nice to change the artboard background color to something else. Usecase would be, for example, I design an iphone app, and I don't want the status bar (top 20px) to overlay the design, so I give my "header" a top of 20px and end up with a white bar, whereas I might want to have a different color there.
You could add a box in the color you want at 20px high, or a full size box in your color and add the rest of your ui in there, but setting the color of your artboard would be simpler.
@kilian I agree to the value of this functionality within SubForm, and would advise you on two things:
It is my belief that in the process of doing step two, you are highly likely to discover other - potentially more important - features or bugs within Subform that Kevin and Ryan can address before addressing this request. If you don't, and instead are able to quickly and easily prototype this functionality within Subform, do it again and record your process so we can all learn and get more excited about the potential of this software!
Adding a 100% width/height freeform mode box is a good solution.
The reason we didn't want to allow style properties on the artboard is because we wanted to leave room in the UI for other, artboard-specific functionality: file export presets, overflow behavior, etc.
Re: "simple", we thought it'd be better to reinforce that an artboard is a different kind of object than a standard element (and doesn't have all of the style properties).