I think you’ll find that the scope for new factions with truly unique styles of play is truly limited until you begin creating weird factions that require the addition of strange new rules to make them stand out.
Strangely, this is exactly why some people argued against the addition of fluff in the other thread I posted in yet it seems to me that the existence of world fluff would actually work to keep the game mechanics tighter and more consistent.
I don't see how your final stipulation has any bearing in reality. For the most blatant examples, you may wish to revisit GW's various Chaos armies. It is impossible to sustain the notion that fluff can actually improve game mechanics, all it does is complement the gamer's experience. Or how about the 6th ed High Elf rule that they had to randomly select a general for each battle b/c "... High Elves love intrigue and politics. Unfortunately, this sometimes means that their armies are trusted to the care of individuals on the basis of the political faction they follow rather than their ability to lead" (Warhammer: High Elves
2002, pg. 6). This not only an example (one of many that litter GW's games) of a rule stacking upon a rule (eg: the need for "general" to begin with), but it's also an example of rule that flies in the face of logic and army construction (i.e.: "if you want a high leadership general, forget about it b/c he might just be some schlep ... sorry about your battle line; go get an archmage instead").
Given that fluff is probably the least manpower intensive factor possible I’m not sure it’s really a question of having to choose one over the other. Again, I think the continued addition of new and exciting factions will in the long run irreparably hurt the gameplay of the system
Yep this is just the exactly wrong attitude to take. Fluff is not "the least manpower intensive factor possible." Authors spend years on their manuscripts: brainstorming, researching, drafting, revising, reading, asking for outside opinions etc ... . Good fluff is not something you pop off your keyboard and throw into an army book; good writing is not something any Tom, Dick, or Harry can do b/c they've read a few books here and there. New factions that are have poorly conceived and written rules will hurt the game in the long run (re: GW); it has nothing to do w/whether there's fluff backing them up or not. Good systems are good systems; they don't need fluff to make themselves work (re: Puerto Rico).
“The idea of Hannibal's Carthaginians facing off against the Umenzi is very cool.”
And completely feasible given that the two systems will be compatible. Should your view that the fantasy setting can freely disregard and background be taken as an argument for ignoring any historical accuracy in the Roman/Carthaginian factions?
Guess what? BG has, to date, pretty much zero background and we've all come to their game system eventually anyway. So yes, a game can freely disregard its fantasy background (code word: fluff) and be successful (re: Heroquest, Dungeon Twister, Talisman, etc ...). History does not need to serve the game in the way you imply. It can simply be the muse for a new army. For example, Numidian cavalry can be introduced to the game w/out needing to get into any historical minutiae about the origins & specifics of the unit. The game unit just evokes their tactical flavor (very fast, hard hitting, but very fragile and unable to sustain long engagements = requisite stats & point cost). So it's a matter of how accurate you want to get, but the more accurate it is the more ponderous and suseptible to abuse it'll be.
So on the one hand you feel the addition of Demons is just getting silly and yet you’re arguing for the game to be kept a simple as possible with the absence of any fluff and the possibility of Roman/Elf crossovers?
In short. Yes. If the game system can support a Roman Legion vs. Elven Legion battle, yes. I just don't like how GW has implemented the Chaos aspect of their fluff in their rules. That's GW's mess, and I'd like to see BG flee from that "model" of how to construct the conflicts that will drive their mythology. Yep, that's personal preference you're sensing there.
Considering Manichean theology rejects the notion of the embodiment of a good/evil duality it’s actually far less simplistic than the dominant world religions. Personally I’d love to see a fantasy world influenced by the ideas of braneworlds and supersymmetry but accepting the fact it has to have some mass appeal I find it hard to criticize GW’s rejection of the clear-cut designation of good/evil fantasy races in favor of the wider notion of corruption vs. puritanism.
First, there are many garbs assumed by Manicheism, from the Cathars to GW, but we'll just stick to the basics. Manichean theology is "far less simplistic" in one sense: it attempts to synthesize them (from Buddhism to Zoarastianism to Christianity) under one umbrella, so that it has to negotiate a wide array of conflicted philosophical and theological systems. Unfortunately, the only "umbrella" that can even begin to hope to reconcile such widely divergent faiths is a simplistic dualism that reads like poorly written "fluff:" an overarching struggle between "light" and "darkness."
St. Augustine, among many others, has deconstructed the underlying binary faults of their dualist philosophy; I'd encourage you to reread some actual Manichean texts and Augustine to get a better picture of a religion you mistakenly believe is "far less simplistic than the dominant world religions." Then try to sort out the doctrine of the Trinity or Nirvana; you won't be able to (no one else has). Why? B/c dualism is simple the other stuff is not. It is the most simplistic religion b/c it is dualist. As a basic rule of thumb, when anyone can actually make sense of a theology it's very simple. When the best and brightest (Augustine, Aquinas, Rashi, Milton, Dante, Hegel, Zizek, etc ...) of their day find it engaging and struggle with it, like the Trinity, then not only is it not simple but it's also significant.
None of the other major religions are conceived from the ground up on such a simple premise. As a brief primer, "Satan" doesn't enter the Western monotheistic religions until relatively late and even then he's a beaten nuetered version of what you find in Manicheism; Elain Pagels can help you out here. And, none of the major Eastern religions is built dualistically; Hinduism is a layered pantheon and Buddhism is borderline atheist at all.
Nevertheless, this is all to say that I don't find fluff built on dualism to very interesting at all (yep, personal preference). Furthermore, the major game system that many of us leaving to come to BG and other games--cough ... GW ... cough--is built upon fluff hashed out by a handful of 20 somethings w/nothing to do but play D&D all day, and the way this fluff affects the game play of their systems, as reflected in the army rules (I've already said the base system is an outdated beast), has become a liability to the development of their game system. I'd simply like to see that BG doesn't even start to go down that road ... it's treacherous.
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