on the pro it is moving 2x the pixels ....
Actually the MBP is moving 4x the pixels.
MBP: 1600x2560=4,096,000 pixels
MBA: 768x1344=1,032,192 pixels
I replaced my 2008 15" MBP with a 2011 13" MBA. I loved it, but after awhile realized the 11" MBA was what I really wanted. So I got a 2013 11" i7 8gb/512gb MBA and it has been my primary computer ever since. At home it's usually connected to a big screen, external keyboard/mouse, USB audio interface and a variety of other peripherals.
I retired a few years ago, so my pro software is getting old but still meets my needs. I run Final Cut Pro, Logic Pro, Strata 3d CX, Vue Infinite, VectorWorks, PhotoShop, FileMaker Pro and other demanding software. The MBA handles it just fine for my use.
A retina screen would add nothing for me. The dot pitch on the 11" screen is already very fine, I can't imagine that more pixels would be useful and it would probably create problems with my older software.
Still completely happy with my 2013 MBA and don't see any reason to upgrade.