You really don't need to worry about light arrows at this point.When getting started,your hunting setup is more than adequate and when shooting hunter class,really all you need.That class is supposed to be more about fun than competition anyway,but you will find many that don't see it that way.I believe the hunter class still has a 35 yard max and faster arrows are really not going to be nearly the advantage that some would lead you to believe.You still need to judge the target right whether the arrow is traveling 240 fps or 270 fps.
I have been shooting 3-d for a long time and I do have a bow setup with light arrows and a moveable sight and long stabilizer.But I still have my hunting rig that I will take out from time to time set up EXACTLY like I carry it in the woods,quiver and all.I have a blast shooting 3-d with either but my mindset is completely different from one to the next.My scores are about the same with either but I shoot much further distances with my target bow.
My point is that you need to try the game to see how competitive you want it to become before sinking alot of money and time into changing things back and forth.