No, I haven't checked out the numbers using any kind of program. I surely expect that some of you math majors can come up with a better equation that those I presented. I just wanted to post something with the general idea of a rating. How that rating system should work is up for discussion, but it should be done in a way that prevents people from killing alts to boost their rating past a certain point. You can never eliminate kill farming entirely, but you can make it so that it won't give you enough of a boost to land you on the leaderboards.

As for level, I forgot about that factor as I'm so much geared towards end game. However, a good idea would be to factor in the level along with the rating in some kind of formula, so that a player fighting another player who is higher level than him has more to gain, while the higher level player has more to lose. And maybe apply a limit of 2 levels just like PvP currently has, so you cannot fight anyone higher or lower than you by more than 2 levels.

The idea is to encourage people to want to fight players who are better or higher level than themselves. Otherwise you end up with a system where nobody will want to fight the best players. You can accomplish this by making such a formula where the potential rewards are higher when you fight a player with a higher rating, or who is slightly higher level than you are. Just as we all love fighting in elite dungeons because the drops are better, people will be lining up to fight Predator even though they know the chance of beating him is small, because he has a 999 rating and if they beat him they will receive a big boost in their rating.