While writing my recent post on Birthright, I got to thinking about other settings that could use its model of domain play, reskinning concepts appropriately. These ideas aren't fully fleshed out by any means, and I don't have immediate plans to run either of these - though developing a riff on Birthright's domain play could be a useful rules module for Quintessence.
The Psychic States of America
"Psychic spies from China try to steal your mind's elation..."
In this setting, characters struggle for psychic control over the American populace using psychic power, the news media, government surveillance, and corporate marketing. So, you know, any time between 1950 and the near future. The holdings are relatively straightforward in their translation: government surveillance replaces Law holdings, corporate marketing replaces Guild holdings, news media replaces Temples (because I'm not actually cynical about religion), and psychic power replaces sources.
Likewise, it's not too great a stretch to use county lines as province boundaries and state lines as (starting) domain borders. The slightly more complicated re-skin is in the province level and magical power of each region, and the replacement of bloodlines. Unsurprisingly, this setting has no concept of the divine right of kings found in Birthright. The math underlying provinces is a bit changed as well: instead of (province level + magical power) being based on terrain type, my thought was that the total number they're split from represents population. Replacing province level, we have Control; replacing magical power, we have Chaos. Government surveillance, corporate marketing, and news media push a message of docility and order: useful for raking in cash and exerting one's authority over a conquered populace, not so good for spreading one's control to another area (since you need psychic power to fuel the supernatural stuff and assert your message over that of a competing domain).
The big thing I'd need to work out is thematic unity between the modern-day paranoia and the inter-regional expansionism. The likely direction here is for players to be something other than government officials, and the "military" that they command is something more unconventional. One possible version replaces the D&D character classes with MiBs (fighters), hackers (wizards), journalists (clerics... ish) and marketer/lobbyists (rogues). Like I said, there's a lot of tonal tweaking that would need to happen. One of the more cynical conceits of the setting is that even the counterculture is co-opted into the scheme of rulership and exists more to undermine enemies than to free anyone's mind.
All of the domain rulers are psychically gifted, replacing bloodlines. They receive a starting Psychic Power score. They gain new powers as this score increases, and the lower of Psychic Power or Authority Points derived from holdings determines their actual budget of Authority Points for the turn. I don't know what different flavors of Psychic Power there might be to parallel the separate bloodline derivations, but figuring out more of the conflicts players engage with would have to come first. Funny story: I'm not at all good at spinning out a whole setting by myself - I'd love to see the Comments section filled with awesome ideas.
In a lot of ways, this setting is a psionics-rather-than-magic, domain-management take on System Sans Setting's excellent Technocracy writeup. There's no reason it needs to be psionic rather than magic, either - that's just what occurred to me first. The concepts he plays with in that post - the imposition of order to counter Threats From Beyond, and enlightened despotism - puts a much more palatable and heroic spin on the whole setting.
The heroic parts of the game also emerge in the parallels of Birthright's monstrous awnsheghlien: the fear and superstitions of the people deliver psychic power to things out of urban legend and conspiracy theory. You know, death panels and so on.
Below the cut: playing with an idea for a magic-focused domain-management system for Dust to Dust. Note: Any information discussed here is a setting reinterpretation and not canonical.
The Domains of Shadows and Dust
"He's a ghost, he's a god, he's a man, he's a guru You're one microscopic cog in his catastrophic plan Designed and directed by his red right hand..."
In this setting, the Principalities, Counties, Provinces, and so on of Dust to Dust teeter between order and chaos, open dominion and secrecy. This game is set well before the Day of Legend in 1211 RE, as it focuses on the struggle between lawful authority and those who move in the shadows. There are evils shrouded in secrecy as well - but perhaps it is only there that one can do battle, before the enemy grows strong enough to work openly.
This re-skin changes the context of province level and magical power, again turning away from terrain type and toward total population. Province level becomes Dominion: the control of the state, state religions, and state-sponsored monopolies over a populace. Magical power becomes Mystery: the power of thieves, wizards, mystery cultists, and outcasts. The function here is complicated, and I haven't thought it out all the way. Part of the requirement, though, is that reducing Mystery in one province (in order to increase Dominion there) requires* increasing Mystery in a neighboring province. Ideally, an enemy's province. Further, as in the core Birthright Rule action, the higher Dominion gets, the harder it is to increase. A ruler can also voluntarily increase Mystery; normally it increases at the cost of Dominion, but if you're trying to expand the populace, you can attempt a more difficult action to increase Mystery without decreasing Dominion.
*Increasing Dominion without transferring the point of Mystery elsewhere is more difficult (higher DC on the Rule action), and not absolutely desirable. There are a lot of things even a Legitimate power would want to do that benefit from Mystery.
Holdings of various kinds may be either Legitimate (capped by Dominion) or Hidden (capped by Mystery). Most law holdings are legitimate, until you get into thieves' guilds replacing the law and enforcing a code of silence. The division shows up more in guilds (craft guilds with a royal charter versus thieves' guilds) and temples (the Redwood Throne, Pentaverate, and similar state religions on one hand, versus the mystery cults on the other). State-sponsored ritualism is completely unknown in this era; even in lands where the ruler is an openly-practicing wizard (such as one-third of all monarchs of Oresund), they do not share power. There have been attempts at state-sponsored wizardry before, but each of those has collapsed.
On a rules level, the reason for this collapse is that ritualists and other researchers need high levels of Mystery to pursue knowledge. Libraries are focal points of secrecy as well as learning in Dust to Dust. The mystery cults, nigh-tautologically, require Mystery in order to exercise their supernatural power. They reveal their secrets only to the Initiated. For this re-skin, ritualists, legitimate temples, and hidden temples gain access to large-scale spells, in the same vein as Birthright's Realm spells.
The concept of bloodlines doesn't fit into DtD, so I'd replace that with a simple Leadership Score and leadership abilities. I might or might not come up with multiple styles or derivations; ultimately this setting de-emphasizes this part of Birthright in favor of the balance of a province's stats. It's common for neighboring powers, and domestic powers with opposing interests, to interfere with one another with the sowing of chaos. I'd want to explore these mechanics further if I were going to run this, with an emphasis on Mystery allowing the covert movement of forces, opposing Espionage actions by Legitimate powers, and the ways the forces of evil use both Mystery and Dominion to affect the world.
There are, of course, plenty of villains in the world to replace the awnsheghlien, though if I were to run this I'd introduce new mid-level villains, to cover the general dormancy of DtD's arch-villains during the earlier centuries of the Regnal Era. That's what I get for adapting my existing setting - I'm firmly attached to the setting's continuity, and some kinds of new introductions would ruin my own enjoyment. Going earlier, into the Truce Era, might be useful for me - a lot of that history is not specifically revealed and that would leave me with more room to maneuver when it comes to the good-vs.-evil conflicts.