I think it is unlikely that you are carving. If that is really what you are interested in (and you should be), you need to take wrathful's advice and go for a bigger board. I am 200lbs and ride a 164. If you want to carve and maybe do some off piste, a board in the 160s just doesn't have the effective edge / surface area for someone of your, umm...mass.
If you are in fact carving, the sacrifice of a smaller board will be that you will wash out much easier in all but the best groomed conditions. You will also have poor float in powder leading to many more cartwheel to scorpion incidence. Since chasing pow and searching for that perfect rail to rail carve are the only worthwhile pursuits outside of the park, you would be doing yourself a disservice.
Also, be aware that with the flow step in you'd be sacrificing some of the response of a strap in binding.
See this thread for the difference between carving and skidded turns.
It's sounds like you already found a great deal on a board. It's won't be such a great deal when you realize you should be riding something much bigger in a few months. Good luck!