Together with KiPart, SKiDL is definitely my favourite KiCad companion, well done indeed xesscorp 
One killer feature for me (if not already in the works/thinking) would be panelizing of gerbers as a last step of the whole SKiDL workflow/api. I’m currently using a SVG/Inkscape hack to panelize my boards when baking them at home:
$ cat crop_svg.sh
#!/bin/sh
inkscape -g -f `pwd`/kicad-plot-SVG-F.Cu.svg --verb=FitCanvasToDrawing --verb=FileSave --verb=FileClose --verb=FileQuit
Combined with a simple HTML file in dire need for Jinja2/templatization:
$ cat panelize.html
<html><head></head><body>
<object type="image/svg+xml" data="kicad-plot-SVG-F.Cu.svg"></object>
<br/>
<object type="image/svg+xml" data="psone_grafitti-F.Cu.svg"></object>
</body></html>
I have little clue how easily hackable gerbers are to achieve the same goal (panelize), but since the topic has been brought before on kicad forums I thought it might be a nice wish, combined with proper/automated management of mouse bites between boards, it can really be a huge time saver for both users and fabs, IMHO.