A thought i had about Kezan as it's own expansion (this is just loose ideas nothing really all that well thought though). It would be more like Panda initially lacking a main villain at start but later be shown. It would give Goblins and Gnomes much needed lore etc. The main theme would be Tech and it's place against magic and other sources of power
With the World healing after the Cataclysm The Steemwheel Cartel have moved to reclaim Kezan in a big way. On this venture the Horde have sent the Biglewater Recolonisation Initiative to claim back the cartel lost holdings and the Alliance have sent the Technology Advance Foundation a group of the more mechanically minded races of the Alliance mostly Gnomes with some Dwarfs and Goats) to study goblin tech to improve the alliance own understanding. Something of a technological arms race between the factions. However in the absence of the Goblins forces have moved to conqueror territory.
As the Expansion goes on the Player would be "tricked" into aiding a shadow faction into raiding a titan facility (http://wowpedia.org/Shrine_of_the_Ancients) and other troves of technology. The Faction called the Machinists would later reveal themselves made up of member of traitor tinkers and engineers from the Horde and Alliance (some of which you'd have quested for over the expansion and know well) who seek to overthrow current factions in the world to place a Technocracy using the tech gathered by the players over the cause of the Expansion. Scenarios could included and attack on Darlan.
Zones _ Kezan it's self would become a "continent" smaller then previous ones
1. Resort Springs – Once a Goblin’s Idea of a paradise however the devastation wrought has the land broken. The regions severed as the main area for hosting guests in Kezan with its two largest ports Edj and Bilgewater Port on either side of the region it act as the entrance to Kezan. As the Bilgewater Recolonisation Initiative move back into their old homes and the Technology Advancement Foundation take up residence in Edj to use it base the factions prepare to take the riches of Kezan for themselves. Venture Corp have a occupied the region and act as the main villains in the region as the questline involve establishing a presence on the island. Think Golbin Malibu with lots of pleasure places and the like
2, The Troll Wilds– With the Goblins mostly gone the Trolls of Kezan with the help of the Zandlai have taken to healing the land due to the fertile soil from the eruption. Now a dangerous tropical jungle lurking with savage beast and more brutal trolls the returning Goblins fear the dark corners of the jungle. Here the player would try to dislodge the Zandali as they try to take Kezan back for themselves.
3. Ashlands - Region most effected by the eruption and is still a fiery waste land where fire elementals. Some Goblins survivors have formed a fire cult and to worship their god in the mountain, they plan to burn the rest of kezan.
4. The Black Coast – The area is named for its abundance of oil. The environment down the coast is ruined as large mutant animals affect by the toxic waste stalk the sands. Large off shore oil rigs barley functioning after the Cataclysm litter the shores. The black coast is profitable and Dangerous. Venture would also feature heavily in the Zone.
5. Kajafields – Kezans greatest veins of Kaja’mite are found here. Maybe Shollzar like factions were you side with one of two rival mining corporations. Completely different story depending on the one chosen by players.
6. Kajaro Heights - The mountainous regions of Kezan possible with a ski resort and other dangers but scars from the eruption are still very much present of the mounts.
7. Undermine - The ruins of Undermine hold the greatest trove of Goblin secrets. Both factions are trying to curry favour with the Steemwheel cartel has they try to make the city liveable once again.
Core of Kajaro - face off against the fire cult god (a large fire elemental probably one of rags commanders who had avoid fighting in the power vacuum caused by rags death)
Venture Testing Site - Face off against the "superweapons" of Venture and finally Razdunk
Pleasure Palace - Face off against a rogue trade prince personal mercenary army
Shrine of the Ancients - an Island Titan facility
A Goblin Lab with associated factors experiments gone wrong
the Naga Gate on early Maps
Titan facility: New Raid
Return of the Blackfuse company getting revenge for the death of their leader
Final showdown with the Machinists
New Class: Tinker (would fit in with themes of expansion but i have no concepts of how it would work)
Fair Enough people agree it's to small thats fair criticism. But what are your feeling on the concepts etc?