Regarding custom B moves:
At the end of the day, people will rightfully only adapt custom B moves in tournaments if they're understood and obviously taken into consideration by Sakurai and his team when it comes to character balance. (and don't take too long to setup, maybe like mario kart 8 kart customization which is nice and quick)
Examples:
**If a character is designed with slowness in mind, yet one of their specials gives them a 10 second speed boost, then that is not a special that takes balance into consideration - it makes their 'strong but slow' A-moves into 'strong and fast' A-moves, which breaks things.**
Or
**If Villager gets a burial special move that buries the other player for 5 seconds, that will be broken because they can set up their whole down B plant combo for an unstoppable combo. The down b combo is powerful BECAUSE it is hard to pull off - that is how it is balanced. If one custom move makes it EASY to pull off, then the character becomes imbalanced due to one special move change.**
Or
**Captain Falcon gets a falcon punch that comes out faster, but does less damage. However, it still has the same knockback, which is what falcon punch is used for and designed to be used for anyway, so it is still an unbalanced and superior falcon punch.**
These are the kind of things people see potentially happening. Which is why veterans are choosing to step back and wait to see how balanced the stage is before we allow custom special moves. If it's balanced - AWESOME! But we cannot get emotionally invested in the sparkly "custom metagame!" if it results in an unbalanced and broken metagame.
It's not worth it, and it's not that big of a deal either. It'll be a great metagame anyway if sakurai and the tekken team balanced the game at least better than melee and brawl, which is very likely.
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