Something to help spice up the leveling and adventuring would be to have zones that all have specific mechanics that are more indepth then what we've previously had.
Blizzard has said that back in the development of Vanilla WoW. they had planned for duskwood to be so dark, that you needed a torch in order to see a decent amount of area. Another Zone they planned for unique mechanics was supposed to be the azol nerub zone, that was cut and turned into a dungeon. That zone was to be a fully subterranean zone that you could use zone specific mounts in order to climb along the rocky walls and tunnels.
We have had some zones with minor mechanics to them, such as the BC zones that had the PVP objectives that could allow for buffs zone wide. Winter grasp was a fully PVP zone as well, with machines, destructible bases and towers. WoD zones had abilities you could use, such as the artillery, or even mounted combat.
But those zones are only minor.
within the last few expacs, i have found pretty much every single zone and quest to be repetitive and boring. However 2 stood out to me as different.. One was the quest for hunters during legion to recruit Rexxar. The other was one for horde players, when you went searching for Jaina's brother underwater.
The rexxar quest was basically a watered down Survival game that lasted 2 minutes. You had to kill for meat, harvest wood. make a fire and cook the meat to eat.. It was very easy, but it was different so it sparked my interest.
The Horde quest you had to delve deep into the ocean depths where it was very dark. You needed a light to see. Just like the original plans for duskwood! The catch was, if you left the light on, enemies attacked you.. But if you left it off to long, a whaleshark would come and eat you, 1 shotting you. It reminded me of Ark's aberration map. Leaving the safety of the green area with no light would summon the little creatures to attack you, and they were immune to damage. not to mention never stopped spawning. Having a light would make them weak, and stop spawning, but the light would attract other dangers. So you had to manage your light usage.
Im not asking we turn zones into "survival" games like the rexxar quest.. But I think adding zone wide mechanics based on the location and lore would add a bit of flavor and spice to leveling.
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Here are just some small examples;
-Desert areas are so hot, you need to keep flasks of water. without water, you get a debuff that makes you weaker to enemies. The debuff stacks, and after so many stacks, you now start to lose health. There can even be achievements based around trying to kill hard / elite or rare mobs while at a certain stack number, which makes you already disadvantaged.
-Have a vertical based zone. Maybe like floating islands and rock masses. You need to glide to each rock mass. And use thermals to gain altitude. Maybe add cool tricks to the gliding. DO A BARREL ROLL!
- I miss zones that have wandering bosses. Or even patrolling elites. Keep you on your toes! Lets say you were in a forest area. Its dark from the canopy blocking sunlight. The woods are filled with monsters. Or even, assassins.. You as the champion / hero/ adventurer are wanted by enemy factions you defeated in a previous zone. The zone is filled with traps. Some classes, such as demon hunter, hunter, or even rogues can detect them more easily. You would have to avoid them just like the ruins in pandaria with mogu traps. But not only that, the assassins are stealthed and wander around the zone. They have a higher then normal agro radius and will try to kill you if you get to close. They can have the "player" mechanics like the island npcs to make them more interesting to fight as well. And defeating them will give you currency for the friendly faction, but! the more you kill in a shorter period of time, the more aggressive the assassins will be against you. Just like the notoriety systems in GTA / saints row / AC and other games with that same mechanic.
- (credit to this idea to Kralljin in the comments) It was mentioned on how weather could increase magic. There could be a zone where the elementals are at war, and the zone could be unhinged magically, causing random weather effects, some that wouldnt make sense logically for a zone that it originally was. And when a certain weather effect comes into play, magical effects are bolstered. Bright sun / heat wave could bolster Fire magic. Snowstorm could increase frost magic. Then from the dragon boss in vortex pinnicle, Windy weather could either slow, or speed up melee attacks based on if you are upwind, or downwind.
There are many more ideas for zones that could be used. What are some you have?