A trick I've used to quickly scale plan views / elevations / section that I've rendered to look like they are hand-drawn, is to make a 'frame' of simple morph lines with a nice round dimension. Select the frame in 3D (with the rest of the model there of course) and pick 'zoom to selection'. If you make a render after that, you can set it up to have the same aspect ratio as your 'frame' and even render it at about 300 dpi to be excactly on the scale you need it to be.
You won't get sketchy labels or dimensions, though.
On a similar note, to show door swing I've just drawn some morph swing lines for the floor plans.
Circles still look bad though, but can't win them all.
I like mixing different sketch styles together by either hiding layers and rendering with different thickness/pen style, or by turning every thickness to 0% and only rendering the shadows or vectorial hatch, allowing me to oversize the contours, but keep the hatching neat and using a heavy weight pencil style for shadows. Just put everything in photoshop and set layers to multiply.
And sketch renders generally take about 5 seconds to render, so the process doesn't take that much time. Especially if you save your presets as scenes.
Erwin Edel, Project Lead, Leloup Architectenwww.leloup.nl
ArchiCAD 9-26NED FULL
Windows 10 Pro
Adobe Design Premium CS5