If you are seriously concerned about how can it scale (giantic projects and high demandings) then wait and go for a 15' rMBP.
But almost nobody works at 192KHz (only professionals), even most producers or audio editors do it at 44,5KHz (or 96KHz) so it will be fine. Obviously if you're going to work at 192KHz and 24 bits with multiple channels crowded of VST's and VSTi's it won't do. I can run it quite smoothly in my MBP 2010 (with a Core 2 Duo, which is almost 3 times less powerful than the i5 of the actual Air). TOTALLY FALSE that you can't run Logic Pro X on an Air. Lol, absolutely impossible? don't trust those funny resellers as they want you to spend as much as possible.
