I've read through most of your conversations, I'm not gonna quote. I think what I want to say is adressed to multiple persons.
There is difference between 2 people who are both professional PvP players. When it's up to mentoring, it's not only about who is better or who knows more. It's more about the interactions with other people. Let's have some examples:
Say we have a player with professional PvP skills, many awards, massive experience, some nice qualities regarding Elements. But when it comes to interacting with people, he wants to dominate. He looks down on everybody and makes people feel bad. Would he/she be a nice Mentor?
Also let's say we have an Apprentice who just wants help to build a good deck. His Mentor wants to train him to become one of the best players in the world, while the Apprentice has no intention to reach any higher than just making a good deck and having fun.
A third example is a Mentor who knows everything about the game and the forum. Literally. However, he/she sucks at teaching others. He knows how to do it, but he can't explain anything without confusing other people.
The 4th example is another Apprentice. He absolutely ignores the game, for some reason. However, he would really like to participate in Brawl and other Forum Games, but he/she isn't confident enough to start. He/she thinks that it might be too difficult. This Apprentice also has some really nice card ideas, but he haven't even heard about Xenocidius'es card maker tool. He/she would need a different kind of mentor. (here comes andretimpa)
These examples reflect that there is difference between good player and good player, that's why I don't think we should limit the number of Mentors too much. I think the cap should be around ~12, but 15 max. I'm still waiting for Odii Odsen, because he also noted he might want to join.