there has been a lot of talk in the last few years about making a game system Balanced. what does everyone mean by balance, often it means that each class is the same. sometimes it means that each PC can contribute to a season in different yet vital ways. the issue is that there is not a universal concensous on what it means for a Table top rpg to be balanced.
in older editions of games the idea was that a game was balances if every PC could contribute to the game. the old days knew that just by having different classes and races you could and should not create a balance were each class was mechanically equal this would result in sameness and at that point why even have classes. in other words is balance equality of opportunity or making everyone the same.
fourth edition of dnd is often said to be the most balanced edition of Dnd ever and it is also the least successful version of all times. the thing is 4e was balanced by making every class the same. you can call an ability by different names, but it is still a PC using an at will attack that does XDZ+Y. third edition and pathfinder kept using the term balance yet the game was never balanced in either equality of opportunity nor sameness. wizards were the kings and fighter and monk were earthworms. the wizard could do everything every other class could do and do it better.
Fantasy flight games star wars on the other hand is a perfect example of equality of opportunity. every class can if they choose specialize in other classes areas, therefore the players can play what they want with out creating imbalance because every other player has the same XP to buy what they want. Jedi are not super over powered because they have to use their XP for force powers as well as skills and talents resulting in the class either being able to move a droid or becoming good at a blaster.
in the end balance should not be the goal of a system rather the goal needs to be is this game going to be fun for all. 3.p started to become less fun the more players in the group whined about balance. 4e was not fun as it was like playing mice and mystics (which by the way M&M is a good board game, but as I said it is a BOARD game not a rpg). FFGSW is actually fun because they built the system not to be balanced, but to be fun and the balance was just part of the openness they wanted to have in character progression.