Splatoon character might be cool if the game ends up having a story and recognizable characters, instead of just being an arena shooter.
Even without all that it still might be a cool addition to the roster, but I'd rather see other mascots with projectiles first.
team fortress has proved you don't even need a story to have recognizable characters.
Man if they get the shooting right and have other mods, man that stuff might catch like wild fire.