While people requested a
Ered Luin faction in vanilla and about every mods hehe I have and still strongly argue against it. Why?
From lore perspective they [the Broadbeams and Firebeards] as far as we are informed had the same king as the Longbeards since the last 3300 years, when the kingdoms in the Blue mountains were destroyed. Neither kingdom of these are mentioned nor any king.
After the end of the First Age the power and wealth of Khazad-dûm was much increased; for it was enriched by many people and much lore and craft when the ancient cities of Nogrod and Belegost in the Blue Mountains were ruined at the breaking of Thangorodrim.
- Appendix A
ca 40 Many dwarves leaving their old cities in Ered Luin go to Moria and swell its numbers.- Appendix B
After Moria fell we are never told they left their Longbeard regents and some Longbeard kings straight foreward
lived in Ered Luin, the last was Thorin whom we soon meet in The Hobbit, IMO pointing at that the three houses of the West lived togehter just as Noldor, Sindar, Nandor and Silvans did in Lindon; it applies for Lórien as well.
An argument against it is the seven hoards of the seven things referred to been the Dwarven hoards, but that's the only suggestion the Ered Luin-houses would have a king of their own anywhere any longer. However that might be simply a myth, so we will stick to a single Dwarven faction.
It is said that the foundation of each of the Seven Hoards of the Dwarf-kings of old was a golden ring;- Of the Rings of Power and the Third AgeBut are not evil by nature, and few ever served the Enemy of free will, whatever the tales of Men alleged. For Men of old lusted after their wealth and the work of their hands, and there has been enmity between the races.
- Appendix F
And from a gameplay perspective as the fragmented geographical situation makes for a more interesting, different and challenging campaigns compaired to regulair geographically connected factions.
The so far only reasonable argument for a Dwarven split (more factions for the sake of more factions is not a heavy argument in itself) so far has been the
corruption question, but to create a new faction in the honestly quite sleepy NW corner of the map to avoid corruption seems a bit far going.