Take it easy, and just ride as much as possible, i thought i was quick on a restricted sv, especially when i was out with people from here. got de restricted and started riding with some new friends who left me for dead.
You'll always be pushed out of your comfort zone if you try to improve, it's how far out of your comfort zone that your willin to go that matters.
Take things easy, but riding the back brake will not help you brake in the long run, as all have said, more front than back, but many people have no idea what the back brake is for, i use it in corners as it helps reduce running wide if you're going too fast and you don't wanna use the front, all personal preference really

on your first group ride though