Here are some basic concepts that can be expanded upon and refined.
Explorer
The airship was an opportunity too immense for some men to resist. Faced with the impenetrable wild explorers set out to make all things known to all men. Equipped with the latest in navigational tools, weighed down by the tonnes of star charts/continental maps/and ancient scribblings, and decorated with the unusual and forgotten relics of lost civilisations, an adventurer is always prepared to venture out into the unknown currents of the skies.
Merchant
The winds carry more than an airship, they carry the fortunes and hopes of empires. An explorer may make a new way through the untamed clouds but a merchant carves out the deep roads. Loaded with various crates of exotic spices, seasonal foods, warm furs, essential machinery, and whatever is in demand, the men of the coin are the backbone that keeps civilisation standing and its purses full.
Doctor
As the reaches of a nation expand further out, a simple error for those living in the boarder lands can easily spiral from minor consequences to life threatening. However, the infrastructure isn't strong enough to support emergency services in every town, so mobile airships are modified to meet the need. Prepared for every crisis a mobile hospital comes complete with life support gear, on the field surgery room, precious medicine, and winches for remote rescue. They are the true angels of the heavens.
Scientist
The pursuit of knowledge is a feverish pastime and those who dedicate themselves to it are quickly absorbed by it. Jerry-rigged observational equipment, weather balloons, heavily worded text books, technical instruments, and arcane electrical coils are all strapped onto the hulls of ships and launched out into the eye of the nearest storm to gather as much data as possible. For these brave or foolish men a life without knowledge is more dangerous than life without risk.
Nomad
For some men there is no home to go back to, no national banner to live under, no way to go but forward. Drifting lazily through the skies their airships are more than just transport they are a home to live in and to protect. The comforts of every home adorn each nook and cranny with small trinkets, portable beds, kitchenettes, and relaxing chairs overlooking the vast mountain ranges and fading sunsets. A nomad is not homeless or lost, poor or barbaric, they are complete wherever they are.
