+1. Very good reasoning.wow, that is a beast of an MBA! Obviously it is subjective, but for me it is a no-brainer... MBA. I think that the multiple ports will come in handy, especially since it will be used by multiple family members. And with school-age kids, you'll probably need to regularly have multiple devices connected to it like a SuperDrive and thumbdrives.
Regarding the processors, the MBA will be able to do everything and more that the rMB can, but the difference is the MBA won't break a sweat over it.