[New to Shadowrun] Questions, Altering the backstory & incorporating Horrors Options

[ProfessorPhobos]

I played Shadowrun briefly in high school many years ago, and didn't really give it a second thought until recently when I saw DriveThruRPG had the core PDFs for $50 in a bundle, and the corebook itself was only $15. I figured, why not?

Well, I was pleasantly surprised at how much I liked the corebook. I think elements of the Shadowrun game are a little hard to take seriously, but...in all honesty, I've come up with plot hooks by the dozen in the short time I've been reading the corebook and skimming the supplements. Whatever the faults of the backstory, the game more than makes up for it by having an intuitive, compelling hook for scenarios and characters.

So I was actually going to sit down and get a basic campaign outline done so I can include it on my next prospectus. I give my group a list of campaign ideas I think I could run satisfyingly and they vote on which one we do next; I usually like to have at least the basics of a campaign "ready to go" at that point, to be later modified in the face of the characters produced by the players.

So I had some questions. Mundanely...of the additional rulebooks (Street Magic, Runner's Companion, Arsenal, Augmentation, Unwired) which are the most necessary? What should I watch out for or be careful with? I haven't given them a detailed perusal yet and probably wouldn't unless I actually had to sit down and prepare a campaign. Of the other supplements, which are the best/most useful? I'm definitely considering grabbing Vice and Seattle 2072, but what about Running Wild, Feral Cities, etc?

Perhaps more contentiously, certain elements of the backstory I just cannot accept. Specifically, an insurgency of Native Americans against the US government and concentration camps, etc. I was thinking of having the Native American Nations being a more direct consequence of the awakening. Specifically, very powerful nature spirits woke up and demanded that descendants of allied/favored tribes be placed in actual political control over what regions were still mystically active enough to fall under their dominion. So this basically creates the NANs, not after a protracted, bloody conflict, but just as a metaphysical necessity- the US government couldn't fight nature itself, so it gave in and ceded territory. I'd add many more exclave cities like Seattle or Denver; Phoenix at the very least, probably also Portland, Vancouver, Edmonton, Calgary, Salt Lake City, Las Vegas etc- any area heavily urbanized would be no longer in the magical territory of the nature spirits. The NANs immediately granted citizenship to anyone with even the slightest trace of Amerindian blood, everyone else emigrated to US (later, UCAS) exclave cities, forming heavily urbanized and densely populated sprawls. The NANs don't have an ideal relationship with the UCAS and are genuinely independent states, but the relationship isn't outright hostile and there's travel, economic integration, etc, between them.

I was going to include a NATO/EU like entity called the "Denver Treaty Organization" integrating very high level policy between North American states, including a defense partnership. I'm curious to know from Shadowrun experts how much this would break the backstory- the borders don't change, but the political situation in North America is perhaps less volatile. Since I don't want to really mess with the world map too extensively, I figure Tir Tairngire's creation is actually considerably less well-received than the creation of the NANs and the UCAS, but when you've got dragons and ancient magic and super-elves and such, people make compromises.

The other thing I find highly questionable is the Confederated American States and the California Free State; it doesn't seem like California benefited much from seceding since it seems to get the ever living shit kicked out of it over and over again, and the CAS couldn't even prevent a whole swath of Texas being annexed by Aztlan. Since I don't want to screw with the map too badly, I was going to leave CalFree as part of the setting but just ignore the CAS entirely. Does this break the setting all that much? Alternatively, I could just have the UCAS/CAS breakup be fairly amicable and both are strong allies and mutual members of the DTO, but that leaves it a mystery why Aztlan could annex parts of Texas without triggering a war (How did they manage that, anyway? I must have missed it in the history chapter). I know balkanization is a part of the setting designed to increase the pre-eminence of the megacorporations, but it really feels like the United States got hit with the Hammer of Plot over the course of sixty years, to a degree that feels even more unbelievable than cyborg elves.

Anyway, my last question is about the connections to this "Earthdawn" game, which I've also been considering recently. I wanted to work the Horrors in somehow to any Shadowrun game I'd run. Is there a book that has stats for them or descriptions? Are the Earthdawn rules compatible with the Shadowrun rules?