Thats pretty good results you got there, i wouldnt mess too much more with it,at least for a bit
I ran 5.5g's for ages and found they worked well for me, recently went to 5.1g's which were betterbut after i re-fitted myopen filter and messedwith that i think aybe i might go back to 5.5g's cos i feel im revving too high at times.Think the open filter etc has free'd it up a bit maybe and the 5.1'smay be just a tad too lght now.
Just back from holiday yesterday so not had time to do any tuning/messing about yet but will maybe get some time tomorrow or during this week.
The shorter boss does helptp end,i got 3-5mph afteri shortened mine down.