So considering Sargeras is the size of a planet and the single most powerful guy in the universe it seems very forced for us to actually kill him in the Argus raid.With the recent info that the Void is the greater threat i've had this idea of how we could actually work with Sargeras against the Void.
As the final bosses of the Argus raid,we face either the Nathrezim High Council or both Archimonde and Kiljaedan in a team fight. We finally beat them with help from a lot of major lore characters.While we are on Argus,Sargeras manages to finally arrive at Azeroth.He is waaay too powerful for us to defeat so we are forced to make a pact with him.He will spare our planet if we are willing to serve him as his new Legion.We will invade worlds corrupted by the Void and conquer them in his name.Sargeras names it the Army of Light to mock as and Velen's prophecy comes true with a cruel twist.Also to instill fear in us he cleaves our moon,The Pale Lady,essentially killing Elune(whether she stays permanently dead can be changed later on).
The first duty he gives us is weed out any Old God presence in our own world so as to keep the titan Azeroth away from the Void Lords.Sargeras casts a spell on the Titan so that it never wakes up.
We basically become a space faring army working for a Dark God,who we hate but is forced to serve for our planets' safety(Silver Surfer basically).I personally think this would help to tell some very interesting stories,while having an option to introduce new worlds whenever needed.
Thoughts?