Not to sure about the grading system, but, surely it is worth a try, it does seem to give the teams more scope to build their teams, and I recall that Coventry had to make a choice between Hamill and Hancock not long ago, so, the Wolves situation with the brothers is nothing new. Also, the averages do get a bit complex.
The Golden Joker rule is a golden joke, starting from scratch for DOUBLE points! this has been used in the SWC, it robbed the Aussie's of a deserved win last season and I seem to recall that it cost England dearly at PB the previous year, the original rule has been tried and trusted over the years, so why change it?
The weakness of this rule is that it can produce false results.