I agree with basically everything you're saying and one does have to choose whether a 0.6 lb difference is worth all of the sacrifices, and for me that's not the case, for you it is, so that's a personal matter.
However, I still think the MBA is the worst value. If you want an even lighter/thinner option that also has a Retina screen then you can get the MacBook. The only advantage the Air has is price, but it's only a couple hundred dollars and you're not only sacrificing the screen, you're also getting half the storage space and getting slower storage/RAM. Right now Air is the odd one out to me because the MacBook is everything that computer should be.
Ah, yes, the rMB.
I have debated this ad nauseum elsewhere, as many have suggested the rMB.
When the MBA was first released, in 2008, it was a sleek, revolutionary design, and boasted a stunning appearance, and form factor.
It was also seriously underpowered - the first generation of that thing had 80GB HDD or a 64GB SSD, the same that the flagship iPod Touch had. Moreover, the battery life was poor.
While I adored the form factor, and the portability - I am a middle aged professional female, and weight matters to me - I was not going to invest in that computer until its specs, and power improved. My first MBA - which I bought in late 2010 - was the so-called Rev C - it came with a 128 GB SSD, and 2 GB RAM.
Fast forward a few years, and the specs improved exponentially. My current MBA is a Core i7, with 8 GB RAM and 512 SSD, and is a stunning machine which gives me power, portability and a battery which lasts a full day. Yes, I accept that the screen isn't the best in the business; but, that is not my priority - portability, power, reliability and a great battery are of far greater importance to me.
To be honest, until and unless the rMB is beefed up, I haven't a notion of looking at it; it is like the 2008 MBA, an over-priced, underpowered computer with a great screen. Now, I have no doubt that in a few years time, - as happened with the MBA - the rMB will be a stunning machine, with the specs I require. That is when I shall consider it.
To the OP, get the refurb MBA if you want the peace of mind of the warranties that come with a new computer and expect to get four to five years out of it. Buy the three year old MBP if you plan to purchase another computer in 18 months; if your heart is set on a rMBP, try your damnedest to buy one as a refurb.
Seriously, while I would accept a three year old computer as a gift (I have given some of mine to my brothers), I would never consider buying one. Ever. Especially if I wished to use it for years.