To be honesty Martin, its seems to me its only you that's wants to change the system. The other 600 + that use it seem perfectly happy and have been for over 10 years.
It may not be 100% perfect but then I suspect no system would be.
You cant use all targets hit unless its single event ie Euro.
As other said, wind in Nefta could be 0 wind and high scores while wind in Wafta could be off plate at the same time on the same day. Scores would be vastly different.
What you should be concentrating on is checking your score card if you want a more accurate grade