Well you have to remember that the iMac also uses laptop guts and mobile GPUs in just as a skinny/cramped/heated environment now as the Retina does. If you've seen the new iMac enclosure, you realize just how cramped they have everything on that board.
I could understand if the iMac used desktop GPUs but it doesnt. It uses the mobile chipset.
It has the ability to do the higher end motion graphics and runs circles around the 'Retina' laptop because it has the 2GB NVidia GTX chipset vs the 1 GB GT chipset. So if they can pull that off in the iMac and that isn't a 'Pro' machine with just how ridiculously thin that thing is, then they can pull it off in the Retina.
That's the issue. A 'Pro' moniker is attached to the laptop while the 'average' user machine doesn't have 'Pro' in it's name, yet has the better 'Pro' specs by a long shot. The most important thing is the GPU for a 'Pro' machine.
I really believe Gen2 will have the 2GB card and Gen1 was literally a 'test' machine.
As for the case, I like the weight of the old case/thickness...makes the machine feel more grounded on the desktop.
Well, The Macbook Retina predates the latest imacs. Even so though, a 21inch frame, a 27inch frame, even if thin, it provides more space than the slender Macbook Retina does. I would expect the next version of the Retina to carry a bump in graphic specs, but I don't see such a show stopping problem as you seem to think there is. I think it still fully qualifies as having the pro tag added to it. You're expecting it to be something it isn't. Just because it doesn't meet your unrealistic expectations doesn't mean it isn't worthy of the title pro. In the terms of laptops, it is a pro model. It's highend. Remember, the low end Macbook only has Intel graphics. Pc laptops of comparable price might have as nice of graphics as the highend Macbook models, but for any number of other reasons they'd still fall short. You need to de-attach yourself from this idea that a laptop is a desktop.
What I do for my day job though, I wouldn't do it on an iMac. I wouldn't even do it on the MacPro, which, well, is a bit underpowered by today's standards. Apple doesn't currently make a piece of hardware that compares to the workstation sitting down by my legs. We'll see if they ever decide to update the MacPro
TL;DR Get a grip man, it's a laptop, not a desktop.