System recommendations for a fantasy game with heavy organization-management elements

[VoxRationis]

So I've been entertaining the idea of running a game where the players are the leaders of a dwarven colonial expedition, venturing out from the ancient homeland of the dwarves for the first time. They'd set forth from the borders of the known world with a set number of NPCs and supplies and do a sort of sandboxy hex crawl until they find a good spot to colonize, at which point they settle and try to build a thriving dwarf hold. The gameplay would be a mixture of this sort of large-scale management and smaller-scale adventuring. The setting, ideally, would be a mid- to low-fantasy one, but with room to build magical artifacts (on the level of the Anvil of the Void more than, say, Heward's Organ). Players would delve into dungeons, defeat powerful enemies, and brave various sorts of dangers in order to remove threats to or acquire resources for the colony.

So what systems would people recommend for this sort of game? On the individual level, I was thinking of something around the level of RuneQuest/Mythras, since I'm playing a game of Pulp Cthulhu right now and that system seems to be about where I want on the scale of realism vs. power (although obviously in the wrong genre), but I don't know if there are good mechanics in that system for managing organizations and supplies. I suppose I could run it in e6 and use the PF Kingdoms and War rules, but something always seems a little off about those rules to me and I'd be spending a lot of my time welding houserules and disparate content together.

[Waddacku]

I have not actually played either, but both Adventurer Conqueror King System and Reign. ACKS is based on Basic D&D with a lot of embellishments, Reign is One Roll Engine. Reign's default setting is pretty out there, though. I've heard good things about An Echo, Resounding for Labyrinth Lord, too, and some of Sine Nomine's other products also include some sort of faction or organization management (Stars Without Number (SF, though) and Godbound (very freeform-y factions, though), for two).

They all vary in crunchiness and abstraction, obviously.

[Black Jester]

If you are going for Runequest, you could probably include a few Elements from Hero Quest which has a very strong focus on community building and how the past of the Clan/tribe etc. forms their current customs. If you know the King of Dragon Pass PC game, you have a good idea how you could implement that in a fantasy game.

The fantasy game that handles local industry and feudal organisation the best arein my opinion either HârnMaster with the focus on a very gritty and plausible world, or Pendragon, where the characters are expected to gain a fief/manor at one time during their career.

[Rhedyn]

Savage Worlds Hellfrost setting has a whole book devoted to resource management.

Ultimate Campaign book for Pathfinder has kingdom building rules that could be used for colonial example expansion.

[Knaight]

I'd actually recommend not using REIGN here. While I love the system and it does fit your personal scale characters quite well its organizational focus is largely on interactions between organizations. This sounds like a logistical dwarf vs. nature campaign, which is a bit out of scope.

If there are conflicts based less in nature, REIGN works better.

[Yora]

I have not actually played either, but both Adventurer Conqueror King System and Reign. ACKS is based on Basic D&D with a lot of embellishments

I've barely read halfway through the first post and immediately thought Adventurer Conqueror King. It has this nice addition of detailed domain managment that is specific to it, but being based on the old B/X edition also makes it particularly useful when it comes to the micro managing of exploration. B/X (though also OD&D and aD&D 1st edition) isn't really designed as a monster fighting game but is actually an expedition game. Inventory management is huge. Character advancement is based on returning heavy stuff back to civilization while at the same time you need the available carrying capacity for your required tools to be able to reach the treasure. And on top of that, maxing out your carrying capacity makes you slower, which results in longer exposure to attacks by monsters and bandits (whose defeat barely gets you any XP). To increase your capacity to carry XP and improve your speed at avoiding deadly attacks, you can make use of pack animals. But these are animals. They need to be tended to and they need to be guarded and protected.
This can turn into a very large expedition very quickly. Under the numbers from the Expert Set (I believe ACKS is very close to that), characters at 8th level and beyond need 30 mule loads of treasure to level up (http://spriggans-den.com/2017/04/14/were-gonna-need-a-bigger-mule/), each. And that's just the treasure. Not accounting for any supplies for the return trip and any tools not left behind.

[VoxRationis]

I've barely read halfway through the first post and immediately thought Adventurer Conqueror King. It has this nice addition of detailed domain managment that is specific to it, but being based on the old B/X edition also makes it particularly useful when it comes to the micro managing of exploration. B/X (though also OD&D and aD&D 1st edition) isn't really designed as a monster fighting game but is actually an expedition game. Inventory management is huge. Character advancement is based on returning heavy stuff back to civilization while at the same time you need the available carrying capacity for your required tools to be able to reach the treasure. And on top of that, maxing out your carrying capacity makes you slower, which results in longer exposure to attacks by monsters and bandits (whose defeat barely gets you any XP). To increase your capacity to carry XP and improve your speed at avoiding deadly attacks, you can make use of pack animals. But these are animals. They need to be tended to and they need to be guarded and protected.
This can turn into a very large expedition very quickly. Under the numbers from the Expert Set (I believe ACKS is very close to that), characters at 8th level and beyond need 30 mule loads of treasure to level up (http://spriggans-den.com/2017/04/14/were-gonna-need-a-bigger-mule/), each. And that's just the treasure. Not accounting for any supplies for the return trip and any tools not left behind.

I'm a little concerned that this sounds like the expedition forms to fuel character advancement, rather than advancing characters as one of several means of strengthening the expedition. Am I wrong in this?

[Beneath]

The "expedition to fuel character advancement" system is actually a pretty simple one: for every gold piece brought out of the dungeon and taken to somewhere you can spend it (or stick it in a treasury/museum/whatever), or acquired by selling things gained in a similar manner, you gain 1 xp. I think ACKS also has its domain-management system work on the assumption that money gained through taxation also earns you EXP (essentially being a treasure reward for holding your domain against all comers).

Getting XP for treasure hauls was a staple of every edition of (A)D&D published with Gygax at the helm and an optional rule in AD&D2 (my starting system). Giving people EXP for sending out tax collectors is somewhat controversial among that community though, though I think for a Dwarf Fortress-like game about establishing, growing, and defending a holding it makes sense.

If you don't have a home base until you settle, then you might have to rework the EXP-for-Treasure system until then, especially if the caravan has highly limited capacity for treasure. Maybe give half EXP for burying treasure caches, and half EXP for retrieving a treasure cache buried earlier (full EXP if monsters find it in the meantime and you have to take it from them again, the downside being that you have to take it from them again), or perhaps by assigning a GP value to information about the lay of the land. I've seen multiple people propose house rules for exploration EXP, though not to the extent you'd want to highlight it in a game about seeking a new home.

If you go with a game based on TSR D&D, an added benefit is that you don't have to worry about things you come up with as low-level EXP awards eclipsing the staples of high-level play, since EXP requirements for single-digit levels are roughly exponential; even if you give out, say, 100 EXP per 6-mile hex entered by PCs for the first time, divided among the party, which is significant at low levels (20 hexes per character will get a fighter to level 2, 20 more to level 3), even a solo adventurer isn't going to be able to gain significant EXP just from wandering around when they need like 50,000 EXP (that's 500 hexes, just for them) to level (EXP requirements level out in the double digits to around 100k/level depending on class)