I decided to get a 15" 2012 2.7Gig i7 MBP but went for the hi res anti glare display over the Retina which is around £450 less so may compare well with the 2011 model price.
Other than the screen it is pretty much identical in spec to the Retina model however it retains the optical drive, has FW800 and Gig ethernet connections as well as Thunderbolt and 2 x USB 3 ports. Since I have a few FW peripherals I still use, made it a lot easier than buying Thunderbolt adapters on top.
The Nvidia site says the GT650M has 384 Cuda cores so as you say it will help with Resolve etc.
I am very happy with the machine, its very quick, it beats my old 8 core MacPro in just about most areas. Might be worth a look for you.
best wishes
Neil
http://www.patience.tv