Please, any Rioter, give me a detailed explanation as to why story, art, and sound should be combined within the same board despite the fact that they are vastly different artistic disciplines?
It doesn't make much sense.
@Riot, what the heck are you doing?
GreenLore2 votesIf you want to talk about a champ VU for example,one that will change the appearance and the personality of the champ. Then would that count as story or art?
Sneak Dog2 votesWhere does a thread about a kit update along with a new model and particles go?
It's a thread about two things. Story and art.
frigginmurlocs2 votesThat depends, if you are talking about the kit changes gameplay, the visual changes, story art and sound, if you talk about both, try the misc board
Impetual1 votesIf you want to talk about a champ VU for example,one that will change the appearance and the personality of the champ. Then would that count as story or art?
Actually you're mistaken:
While a visual update would change the appearance of a champion, is would not change the personality or lore of that champion. That would be a retcon, not a visual update.
Changes to a champion's personality and story are lore/story changes.
Changes to a champion's appearance (in whatever kind of visual medium) should be classified as art changes.
Changes to a champion's in-game kit are gameplay changes.
Is it really that complicated?
Impetual2 votesIf you want to talk about a champ VU for example,one that will change the appearance and the personality of the champ. Then would that count as story or art?
It would be a champion story update happening at the same time as an art update.
Two separate teams producing two different updates to the same champion at the same time.
The story team would have to re-write that champion's story, and the art team would have to redo that champion's art.
Riot would then release both of those updates at the same time, and bundle them together.
Seemingly, there is one update, but realistically, two teams worked individually to create two different products that fit together, those two products being any given champion's story/lore, and that champion's visuals.
GreenLore1 votesThe thing is that that the visual one can influence the story one and vice versa. So it wouldn't make sense to talk about these things seperatly.
For example Sions hole in his belly,is related to his story(its the wound that killed him),but it is also a stylistic choice for his character.
You can't just talk about one without the other.
Sneak Dog1 votesGameplay, story, art and sound all influence eachother. Why would you need to bundle three of them but not the fourth?
Besides, I can easily talk about Sions bellyhole story without caring about the art behind it. I've talked about many story-related things without referencing the art at all. People talk about gameplay without caring about the story all the time.
I don't mind these boards being bundled, I think the sound and art boards are kind of liveless on their own most of the time. But the argument you present here doesn't seem very valid to me.
GreenLore1 votesRioters generally don't really talk about the gameplay of VUs until we know the details already.
And its far easier to talk about gameplay without directly going into storydetails than it is to talk about the design of a champ without going into detail of his/her story. When it comes to a VU,the art direction and the story are much closer to each other than the rest of the others. For example if Taric is going to be demacian,shall he wear demacian armor?Shall he have his own unique armor?If he has a unique armor,why would he have one?If he has a demacian armor,why is he the only one with gems in it?
Impetual1 votesThe thing is that that the visual one can influence the story one and vice versa. So it wouldn't make sense to talk about these things seperatly.
For example Sions hole in his belly,is related to his story(its the wound that killed him),but it is also a stylistic choice for his character.
You can't just talk about one without the other.
I don't disagree with that, however, I do believe that the art should be based on the lore, and not the other way around.
The idea of writing a champion's lore around their art seems kinda backwards to me.
Runeterra is a big place with lots of champions that all should have lore that makes sense within the cannon of Runeterra...although admittedly, Riot is kinda playing things fast and loose with that post retcon.
Anyways, my point is that I believe a the design process of a champion should begin with their lore, since that lore is what makes that champion part of Runeterra. After that lore is decided upon, Rioter's could then draw upon that lore for their artistic creations, and perhaps even modify the created lore as needed to suit their needs.
GreenLore1 votesI disagree with that.
I'd say the general theme is usually the most important thing as it influences pretty much everything about the champ(art,story,skills) and garentees that the champ brings something new to the game thematically. If that comes first then they can strart looking for the place where such a character would work the best.
If the story comes first,then it might be possible that the story restricts already the art direction or abilities.
Take 
for example.
When riot started working on him,they pretty much only thought about making a time-traveling assassin,which led to Ekko going through a lot of designs,some made him more of a mystical being,while others were closer to his current,technology using,self.
However if they started out with the idea of making a time-traveling scientist,then they would have never considered making him a mystical being(likewise if they thought about a mystical being that travels through time,then they would have lost the opportunity to make him technology based). In both cases they would have been limited already when it comes to creativity.
I'm not saying the general theme should always come first,sometimes it is a good idea to start with the lore,especially if they want a champ who has a special effect on the world of runeterra(like 
uniting shurima),however not everyone can have nation-changing effect.
Rito Staff2 votesThen you would have two empty boards, having little to no activity. Story, Art, and Sound is the place to go to talk about the arts.
Also, I almost don't see any Sound related threads, why does it bother you? It's mostly lore and graphic design.