Warcraft IV, would only be released after WoW is done cranking out expansions. I could see this kind of release table for Blizzard:
Next up:D3 RoS
Then: WoW Expansion
Followed by: Final SC2 Expansion
Hearthstone and Heroes of the Storm in between those title releases.
D3 Final Expansion
WoW Final Expansion
Diablo MMO (WoW would probably go free to play if it is still around at this point)
Starcraft FPS RPG, maybe?
After that, an alternation between Diablo MMO and Warcraft IV expansions (with smaller projects in between) . After they conclude, Starcraft 3, WoW 2, Diablo 4.
You left out Titan, which I could see being in there instead of the Diablo MMO.
Other than that, I could accept that schedule.