Actual rMBP owner here.
1. Regarding the Samsung issue: a) it's based on a single story from Korea and b) it's rumoured to occur next year. Hardly a matter to consider in your purchase.
2. LGs do suffer from retention but are otherwise beautiful screens that are superior to "classics" in every meaningful way. I happen to have a Samsung and the clarity, contrast, IPS viewing angles, etc. are amazing (as are the LGs). Honestly, I simply couldn't settle for a TN panel that should have been dumped years ago (especially at the price you're paying). It sounds like hyperbole until you spend a few hours in front of the screen (not, mind you, for 10 minutes in a bright-as-sun Apple store full of reflections and finger-smeared screens).
3. Performance is amazing. Depending on your usage, the SSD on the rMBP adds a level of speed that is noticeable (not just some useless benchmark). Add an SSD of the size and quality of the rMBPs (it's a Samsung) to the cMBP and the price disparity shrinks very quiclky.
4. Thinner profile, lighter, blah..blah. You know all this. Oh, and the HDMI port seems like simple thing to mention but it's huge for me.
Does it have odd production issues? Sure. Creaking base plates, QA issues, and the LG screen come to mind. That said, I also had to swap 3 of the so-called "established and proven" 2012 Macbook Airs for exactly the same reasons.
Google "creaking Macbook Air", "LG vs. Samsung Macbook Air", "damaged Air out of box". This is sadly common to Apple in general, not the rMBP specifically.