Ideally, I think the House of Nobles is running things right now, which is its own can of worms.
In regards as to why neither the Alliance nor the Horde have shown up, remember that when Dalran got asploded by Xalāatath, it took down Azerothās biggest, oldest and most stable Portal Network with it.
It is why we see a long line of Sinādorei fleeing to Orgrimmar, one at a time. It is why the Horde and the Alliance havenāt shown up en-mass, because currently all of our standing forces are still in Dornogal, which means they have to come via ship all the way from the south-east corner of the map, navigate around the Maelstrom, and then sail all the way up the coastline of the Eastern Kingdoms to get to Silvermoon.
Thatās a trip that could take months, even with magical assistance to ensure the sails are constantly full of wind to propel the ships at their full speed.
It took a miracle of the Light to call the Vanguard to Silvermoon, and that mostly seemed to only grab Paladins and Priests, who were already full of the Lightās energies and thus more easy for it to connect to. The kind of magical power to open up a Portal large enough for an army to march through is staggering, and without the Sunwell to power it, I doubt the Vanguard of the Light could have shown up at all.
The thought that Xalāatath went after the Black Blood in Dornogal precisely because it would allow her to A) drag all our forces to one area on the far side of the planet B) take of Dalaran and cripple our magical transportation abilities and C) get us so angry that weād follow her relentlessly and could be led to Kāaresh to fulfill her objectives when faced with a āgreaterā enemy, is rather concerning.
What if the Sunwell/Darkwell isnāt her objective? What if it is just a bonus prize? The essence of the World Soul, mingled with the power of the Light, which can be turned to Void with the right push, which in turn could be used to corrupt the World Soul directly with enough power applied in the right places ā¦