If your current machine is sufficient for the non-iOS/OSX dev work you do, I don't see the value in putting money into it instead of a MBP. I would go for option B, however i'd get a 15" with as large an SSD as you can afford with 16GB of memory. Unfortunately what you get with these newer models is what you're stuck with, and I can tell you that anything less than 8GB on those machines can be a PITA, especially if you start running VMs.