My Foray into Steampunk

I am but an infant standing before an ocean when it comes to the genre of Steampunk, but I am quite excited about the gaming opportunities it extends. A gnome escaping from a train heist by sealing the dining car's door with a glue bomb would be amazing. Or a group of half-orc tribesmen that take down the zeppelin of the local oppressive duke with bows and arrows, yeah, that's the ticket!

I'm a long way from making this a true sustained campaign reality, but so far here's what I know.

The world will be my own (sort of).
The geography will match that of our Earth, but history shall be quite different.
The 'civilized' world at this point currently reside on the continent we call North America.
There are approximately 36 nation-states. The two most powerful of which are the Federated States of Ullera and the Sovereign Kingdom of Rausch, currently allies which share borders.

Ullera sits between what we know as the Mississippi River and the East Coast, going north to the shores of the Great Lakes and south to the Everglades. It is a technologically driven state which in many ways mirrors the U.S. in the 1860s. Magecraft has long been outlawed here, but it is rumored to exist.

West of the Mississippi to the Pacific Ocean spans the vast, sparsely populated Kingdom of Rausch. It's king rose from despondent orphanhood to a high position in the state church, eventually securing royal status by marrying ALL THREE of the prior king's daughters. He is highly respected and quite just.

Ulleran settlers, sick of coalsmoke-clogged cities, set east decades ago on all manner of craft (from dirigible to clipper to ship), but the harsh conditions and violent natives in the continents to the east have prevented Ullera from establishing meaningful colonies.

Gameplay will likely be limited to three player characters at a time. Pathfinder RPG rules will be used, augmented by third party steampunk expansions (mainly 3.0 books, actually). Players will all run gestalt characters (taking the best of any two classes).

Gameplay in the first campaign will include limited options. Greater options will be 'unlocked' as the world is explored (Example: once players encounter Knights of Rausch, the paladin class will become available.)

Players will start in Ullera (in game one), and race/class options will be limited to:

Races: Human, Half-elf, Elf, Gnome, Dwarf, Halfling.
Classes: Barbarian, Bard, Fighter, Ranger, Rogue, Sorcerer.

Magic knowledge available to players will be limited to 3rd level spells until higher knowledge is unlocked.

Equipment: Modified black powder weapons exist. Reloading will take something like two full rounds (anything more will make it little fun for an RPG), which can be reduced by feats and class features.

There's plenty to flesh out here. Hit me up with questions. I'm sure there are aspects I haven't considered yet!