i recently purchased my first laptap and i went back and forth as to whether the retina display was worth the significant additional cost. the deal breaker for me was that the MBPw/ret didnt have an optical drive and it had more thunderbolt connections than other connections (usb/firewire800). i still find the need to burn DVDs (which are still lower cost than thumbdrives) and i have many more usb devices to plug in than thunderbolt.
also, though the retina display is pretty....i couldnt figure out any real world advantage the retina display would give me in my photography. on the contrary, i kind of worried that if the ret display looked so good that my images would seem drastically different when they ended up in print or viewed on client computers.
i ended up choosing the 15" MBP non retina and i am quite happy with it. i would strongly recommend you consider whether the retina display really offers you a gain in your photography or if that money would be better spent addressing lenses.