I am not a great fan of increasing the weight of the bow (not that I can) to fine tune arrows unless the archer is very accomplished and shoots regulary and can handle the extra weight without it affecting their form. I have seen the difference just 2lbs can make to somebodys form and enjoyment of their archery.
To prove a point recently about arrows reacting stiff & weak. At 20yards I was able to make my bareshaft move horizontally about 2.5 feet just by changing the quality of my release and the position of the string on the fingers. You can only tune as good as you can shoot.
Technohippy I am assuming when you wound in your limbs you reset the tiller and limb alignment as this will affect your results.
Changing to floss nocking points, heavier points, less strands in your string will help to make small changes to the dynamics of your arrows and how fast they fly but also a "good" bareshaft result might not be right for you at this stage.
A slightly stiff arrow is a little more tollerent of a poorer release e.g. For this season I decided to put an extra 20gns on my points (ACE's) worried about sight marks I went down to a 16str Fastflight string (from 18) and at 20yards had the best ever bareshaft test I had ever shot - with the fletched and bareshaft touching or within a couple of mm. Yet at 100 yards I could not get a group anywhere near what I was shooting the year before. In the end all I had to change was the string back to 18strands and now my groups and consistancy have improved over last year without any loss of sightmarks, clearly the bow was not stable enough with a 16str string for the way I shoot
My bareshaft at 20 yrds is now 5" horizontal (right, I am LH) to the fletched group. Not where people say it should be but for now it's working for me.