I was looking around and couldn't really find too much talking about it, but maybe I am just not using the right search variables... Here goes anyways.
Has much thought come up in regards to having each of the different Mountainhomes be of a different Dwarven race? The distinctions allowed by such a modification to the current situation could create interdwarven wars due to evil/neutral/good dwarf relations. This concept of course could easily apply to the other races as well, allowing for not just the wild elves we have now, but maybe dungeon and dragons' style drow and tolkien's high elves.
These dwarven subraces could rise from schisms which take place in histories after the death of a king, maybe for whatever random reason, the dwarves in the mountainous region support Thob the Terrible, an insane dwarf with very good noble skills, while the dwarves in the costal region support Tun Jabberwocky, a champion. This split turns one group into two, and may start an all-out war. With this split the two sides differentiate, one going towards madness and brutality and the other becoming more war-centric, maybe opening up the creation of additional weapons for both sides, dwarven thrashers for all! These Madwarves and Wardwarves now have independent policital interaction, though a shared history and initial set of enemies/allies, but the schism allows for two new factions to change the status quo, perhaps these Madwarves become true-blue allies of the goblins, and adopt some of the more undwarvenly traits of their new friends, slavery and murder become more acceptable within the new mountainhome, while the Wardwarves become more resistant to sunlight and enjoy fighting more.
I understand that the political system isn't where it would need to be for such a thing, but perhaps some time down the line, we can look at the Legendary records and see the coming together of two dwarven factions after a brutal war, and it's eventual split into three different cultures due to a horrific volcanic eruption, which just happened to destroy the mountainhome.
There could be all kinds of different attitudes and with work, weapons and skills to be split between the Petty, Disney, Mountain, Wood, Mad, Dark, High, Plains and Sea Dwarves. There is a great deal of possibility within the concept, I just don't know if it's entirely worth the effort, so I'm tossing the idea out.