Although there is never-ending discussion about what CC is acceptable for a starter bike, I will have to state my opinion again. I think that its very possible to learn to ride on a 600cc or bigger bike, given that you exercise proper control of it while learning. Although I had previous MX riding experience, I started on a CBR600f4, and I went to a gsxr750 then to a hyabusa within a year. The bike only goes as quickly as you make it. I agree a 1000cc+ bike is going to be harder to control, but I am still a firm believer in saving the money and buying as big of a bike as you want, as long as you work into it. The reality is that a modern 600 is more than enough bike for anyone on the street, but thats not what matters in the end. What matters is having a bike that you enjoy to ride (for whatever reason...including "curb appeal.") So, if you want a 600 or bigger to start, I dont see any issue with it personally.
I could also effectively argue that not having enough bike is just as dangerous, especially in a place like Atlanta where everyone drives 80 MPH. I remember borrowing my buddies ninja 250 one day and riding on I85. I was more concerned with getting run-over than anything else. Sometimes you need to be able to accelerate out of danger.