I respectfully disagree on both counts.
My contention is that the rMB is most likely an Air replacement, so it would actually make sense to see a "bigger brother" to the current one that will replace the 13" Air at some point. I'm not sure what all you include as the "purpose of the product", but surely small size is one of them. Other than being 1/4" deeper, the rMB is smaller in every dimension than the 11" Air. A 14" rMB would easily be smaller than the current 13" Air, if Apple desires to go that route, since the 13" Air has a 16:10 ratio screen.
As for your second point, well, it's not much of a point. Apple could have done whatever they wanted to. Apparently they chose 2 ports and, most likely, desired to cram as big a battery as possible in there. No reason they can't include more in a larger 14".