2. Consistency
None of these points would matter without one more element. That element is Consistency, and it goes hand-in-hand with balance. Without consistency in the general mechanics of the game, we would be left with characters who were very strong and characters who were very weak. Every champion, hero and fighter needs some sort of counterplay in order to keep from dominating the competition. With a medium that is trying to make a name for itself as an official, professional type of "sport", the games need to present themselves with an experience that is on equal ground for all and fair. They also need to allow the player to know (with a relatively minimum amount of game experience) what to expect; the variables need to be contained into certain areas, such as character differences, stage hazards and advantages/disadvantages. All of these are present in the tradition Fighters and MOBAs. These games wouldn't be as popular as they are, now, if you could just pick one character and stomp everyone, but that isn't to say that mistakes don't happen. No developer can create a competitive game that adheres to these regulations 100%, at least not at launch, which leads us to our final point.