RE: Whats wrong with my setup?
I think some people worry way too much about rest tuning, and not enough about shooting well. You can indeed shoot well with a rest that is not set up the best it could be. There have been pro archers win competitions with some very out of tune bows. If you have well matched arrows that have enough fletching on them they will stabilize in 10 or 15 yards, especially with target points. As a matter of fact, some archers throw thier rests out of tune on purpose to get the arrows to stabilize faster. i have also seen some really impressive shooters that shoot traditional off the shelf with no sights and using fingers. Doesn't leave a whole lot to adjust there does it.
I would guess it is your form, not your equipment. But don't feel bad, I would say 99% of the archers could shoot better than they currently do. Very few archers have absolute perfect form and aiming every time. It is also possible your bow does not fit you very well either. It's difficult to shoot a bow well or have good form if your draw length is too long or your draw weight is too high. Also take a look at how you grip the bow. Is your hand relaxed when you shoot, or do you have a death grip on the thing and torque it when you shoot? You should be perfectly relaxed when you release the arrow. The bow should actually jump out of your hand after the shot. Unless it's a newer one that has almost no shock or recoil to it. It should at least be able to roll off the front of your hand after the shot if balanced well. Get a wrist sling, they help!
Mechanically you could check to see that everything is tight. If your rest or sights are loose, that would cause inconsistancies from shot to shot.
Then check your arrows. They should be straight, weigh pretty much the same from arrow to arrow, be the same length and have consistant spine. You could also check to make sure you don't have any contact issues with the fletchings on the rest, harness and riser. This should be the first thing you do after installing the rest however. Make sure that all your fletching are oriented in the same fashion, if they are not rotate the nocks until they are. ( ei; all your odd colored vanes or feathers point is the same direction when on the bow. Like up, to the left, or down. Which ever gives you the best clearance.) This doesn't make them any more accurate, it just minimizes the possibility of contact issues. After that, number your arrows. That way you can tell if certain arrows are hitting the same spot every time. Say your #1 arrow hits high, #2 hits low right and #3 hits left, but they do it consistantly. Then you probably have a problem with your arrows.
Try shooting less arrows as well. Like three at a time, and rest a little between shots. Take your time and relax, archery is mostly mental. To be accurate you need to be consistant. You have to do the same thing every time from shot to shot. Maybe you can find someone to watch you shoot to see if you are doing something wrong like torquing the bow or dropping your arm after the shot.
Good luck and try to have fun,
Paul