Nice Idea. I think I'll include this in my next kit. Anyway you can dig the current mobile kits to get an idea of responsive GUIs for mobiles.
BTW, two more kits got released just now! You might want to take a look.
Endless Run PlayMaker Kit(http://forum.unity3d.com/attachment.php?attachmentid=66562&d=1378554885)
Screenshot, WebPlayer, Android Build and Store Link (http://www.flyingrobotstudios.com/?p=1327)
PinBall PlayMaker Kit
(http://forum.unity3d.com/attachment.php?attachmentid=66565&d=1378555519)
Screenshot, WebPlayer, Android Build and Store Link (http://www.flyingrobotstudios.com/?p=1308)