I don’t play WoW anymore, and I probably won’t play an Activision-Blizzard game again until Kotick is fired and Blizzard stops being a cancerous mockery of a gaming studio, but a few things.
World Revamp: Consider we have the much-vaunted Phasing System in WoW. It wouldn’t be too hard for Blizzard to just phase the entirety of the old world and, given their penchant for reskinning old models, repopulate the ‘new world’ with enlarged cities, altered creatures and new questing hubs without it being a drastic expansion of resources.
Would it be expensive and time consuming? Yes. Would it be as destructive and exhaustive as the cataclysm revamps? No.
Remove some widgets from the map surface here, replace it with trees and rocks. Swap out the cave there for a mine. Add the cave systems, which are all rehashes of each other, to this mountain and turn it into a crude city. Stop trying to wow the players with shiny new things and instead make the map fun and explorable, add time sensitive phenomena like nocturnal/diurnal flora and fauna that might only spawn or be available at certain in-game times of the day.
Best of all, it’s Phased. The old zones are still there, you can go talk to a Bronze Dragon in the Zone and go back to the previous iteration of the region and get whatever you wanted to get from the area, then talk to the Bronze Dragon again and poof, back into the grind.
Player Impact: Players want to be differentiated from their fellows. Situations like the Horde Rebellion, the Sylvanas Follower/Rebel option, all of these are monumental decisions that, sadly, never really matter in the story.
Players get to choose dialogue options in certain quests and story events. Options give players a -2, -1, 0, +1 or +2 to a hidden system based upon the nature of their answer. Be pro-war, get a -2. Be pro-peace, get a +2. Fall somewhere in the middle, get a -1, +1 or a 0. As the story progresses, your options may not necessarily change the story’s overall arc, but your character becomes known for their choices. Some NPCs may spit when you enter the room, or cower when you walk past. Others may salute, or turn away in shame. Others might toss you a piece of fruit or a mug of ale, or point you out to their children and say “There goes WaffleMunch, Champion of Gnomeragon!” if you pass them by.
Certainly, the story may progress from A to B because of raisins, but still, a simple system that allows players to influence at least how the world around them reacts to that character, and explore how their alts might be treated by choosing different options, could be a very neat way to give players that fun little nod to their choice without derailing the story department into writing dozens of different endings and then trying to tie them all up neatly to progress to the next arc of the story.
The option might also open up new avenues in PvP and PvE scenarios, where NPCs might be friendly, or at least neutral, rather than openly aggressive because of your choices. Hidden vendors might open up if you show naked blood-thirst towards the other faction, or choose a path of peace and tolerance. Leader/Champion NPCs might have unique dialogue options and may offer access to unique seasonal scenarios that might not award ILevel gear, but transmog, pets and achievements to help while away downtime as the devs work on the next patch or expanson.
Player Housing: We have Pandaren Scenarios. We have Island Expeditions. It is not going to be too difficult for WoW to create housing in this situation, and can even have multiple different housing options, including Guild Halls that require a staggering amount of gold to purchase, but might offer exceptional RP potential and, in a pinch, might be used for PvP purposes, having rival guilds attacking each other’s bases without needing to create another battleground. Give players an investment not only in gold and resources, but emotional and pride reasons as well.
AND DO NOT TIE THE HOUSING TO A SINGLE EXPANSION. Make it multi-expansion, make it so that players/Guilds can put in buildings taken from Warlords of Draenor, Mists of Pandaria, Battle for Azeroth and more, if they can find the patterns, scrounge enough resources and convince the faction in question to build the structure for them. Make it tied to reputation, give players a reason to go back and pound the sand in older expansions, give Blizzard more playtime that has fun, that has a meaning, other than boredom and achievement-hunting.