Sorry havent read the entire thread but...
The next thing to add for each judge is "scoring deviation".
Take the average score of the other 5 judges and compare it judge 6 score. Judge6 ScoreDev could be +7% or -5% for example. After say 10 contests judged we can identify judges that score much higher or much lower than average and try to address it. I know at least a couple judges in NEBS land with a ScoreDev of -35%
Or maybe even better write a judge seating program that mixes together judges so high scoring and low scoring judges are evenly distributed across the tables