Balancing a MOBA or RPG Game?

OK, so I have a question for all of you who have some real experience with developing a MOBA or RPG Game... when you are trying to balance character classes with their many attributes from magic, basic damage, armor, speed etc... is there some kind of traditional or standard rpg cookbook / formula or something we should be following to help us properly balance a game that have multiple different classes and attributes to deal with?

I've played RPGs for a very long time since Nintendo Zelda,...

Balancing a MOBA or RPG Game?