iPad Air would be the perfect tablet if not for its 1GB RAM...
1 year ago, I got myself a Mini and it was fine until it started to annoy the crap out of me because of Safari constantly having to reload. Obviously, 512 MB is not enough, but Apple is too damn greedy.
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Yes, with two gigabytes this would be really sweet device, and very future proof too, thanks to the great CPU and GPU.
iOS 7.1 seems to be better when it comes to Safari and tab reloads, but one can only imagine how great this would be with two gigabytes

There would be a truly massive amount of free memory for keeping those web pages in memory, not to mention for (un)suspending applications etc..
One gigabyte of RAM is just greedy, there is no way around it.
Have you considered picking up a second hand 4th gen iPad? If I had known how crappy iOS 7.0.x was going to be on Air, I would have picked a used 4th gen instead.
It is a bit chunky, but the display is just as great and the performance is fine for pretty much everything you will ever do on it. In practise it is just as future proof as this Air I am typing this on. They will keep on supporting the 32-bit version of iOS for a long time and it probably has more free RAM than this, so whatever upgrades the Air gets, the 4th gen gets too, unless Apple starts being really nasty...