In the last two days I've added custom DPI changes and the ability to toggle tablet style apps to my Nexus 7 CM10 kang.
I'm feeling like it's really approaching what I want from CM10 on a 7 inch tablet now. It's a pity in some senses that I think if I was to push my changes back up the line they would never make it through review, but then on the other hand I do like the fact that CyanogenMod stick with a purists view, so perhaps kangs like mine are the right and proper place to allow the user more freedom of choice.
I've attached a screenshot of the new settings with tablet apps enabled in phablet mode.
You can find my ROM here: http://forum.xda-developers.com/showthread.php?t=1938041