I am happy to learn that your experience has been stellar and that you are a very happy camper. When the air 2 is released with 2gb SRAM, I wonder what argument you will come up with to defend apple for skimping on the 1st gen air!
The answer is simple and has been stated numerous times in these kinds of threads. RAM is a comparatively large battery hog. It is the only part of the device that is powered at all times. If Apple were to double the RAM, it could have the effect of doubling the standby power draw, halving the standby time.
Frankly, I'm fine with Apple being stingy with RAM in their devices. Developers have repeatedly proven that given excess RAM, they'll get lazy with their coding, to the point that many simple programs now consume hundreds of megabytes on our regular computers. That behavior would wreck the performance of tablets and mobile devices.
Like some of the other people in this thread, I too own some Android tablets with 2-3GB of RAM, and I can confirm as well that it is no panacea - those tablets have plenty of performance issues of their own, while also having significantly worse standby battery life.