So, I was sitting here thinking about how Blizzard could expand upon the current class/race combinations and I had a thought about how Gnome and Goblin Druids could play out.
A small group of Gnomes and Goblins, having faced Cenarius in battle along side Archdruid Malfurion Stormrage, realized for the first time in their lives that the power of Nature could be the next step to advancing their races. After the Demigod Cenarius recovered from his wounds in the Emerald Nightmare, this group of adventurers pleaded and begged him to take them under his branches, and train them as they once did the Archdruid.
Cenarius was dubious about this at best, but he felt he owed them a chance for their valor and candor in fighting for Val'Sharah and her people. So he made the attempt, but much to his dismay, his worse fears were quickly realized as the Gnome's and Goblin's training usually only resulted in half feathered gnomes entangling furry goblins in the roots of one tree or another, and after only a single day, he banished these poor adventurers from the Grove of Cenarius and forbid them from practicing the druidic arts for fear that they bring about the end of days.
Of course, Goblins and Gnomes were never the type to give up and one special team of elite Goblin and Gnomish engineers came up with the ultimate solution - tapping into the powers of nature by using their machines and inventions to act as a buffer. Thus the Gnome and Goblin Druid was born.
Using mechanical suits fashioned after the aspects of nature, these brave adventurers began to fine tune their ability to wield the powers of nature, and studying along side Tauren, Trolls, Night Elves, and Worgen, they perfected a blend of magic, machinery, and nature into a single transformable power suit perfect for the small stature of Gnomes and Goblins.
From an in game perspective:
Gnome and Goblins alike can use the basic attacks - wrath, moonfire, etc. while simply being a gnome/goblin form due to their limited training from Cenarius, but their true power comes out when they activate their suits and transform. Receiving a special shape shift animation using the electrical aura graphic from Hati, the hunter Artifact Pet, they transform into robotic/metallic versions of the basic forms - Bear, Cat, Boomkin, and Treant. In place of the stag, they turn into a special, mechanostrider sort of thing, and for flight form, a robotic bird/owl.
Just a bit of fun, and it could give an interesting alternative for those that want to play a sort of steampunk druid.