Interesting ideas, especially about the Grigori - I wasn't aware that their language was actually Latin, but rather something similar to it - is ordince any case of ordo, ordinis; and shouldn't the accusative be "ordinem"? Ah - unless you were referring to medicos. I think it's more of an approximation of a Romance language, with elements of Greek. Are those concrete etymologies of the name?
I find the idea of the Doviello being "little" anythings quite odd. It's a strange sort of mix of Hebrew and Romance, the typical double L and and the -el of the names of archangels. I'm not sure I can imagine the Doviello as describing themselves as "little", and I agree that "dove" isn't quite fitting. Two explanations I can think of is that your theory is correct, and this is an ironic name given to them by outsiders that has since stuck, and remained the same while the rest of language has changed, thus losing its original meaning. The language of the Doviello is probably very beastial, gruff and harsh; sounding almost like roars and growls to foreigners. Their own name for themselves might be quite hard to transliterate into English.
"Makóm", as I said, was from a very limited knowledge I have of Hebrew. It probably would be best to use other words, as well. Perhaps for the Elohim, "Elohey Beth" (Sounds too much like "Elizabeth", doesn't it? I suppose it could have evolved into "Elohabeth"), Malakey Makóm for the Malakim, and I'm not sure about the Calabim. Maybe the word for "lair".
The problem with using a Norse name for the dwarves is that the Svartalfar are essentially Norse dwarves. It seems a bit odd to have two races which are usually considered to be the same thing living on the same world. Since the Svartalfar are really an offshoot of the Ljosalfar, it makes more sense to give them the opposite Norse name to Ljosalfaheim. That's why I suggest using the Tolkien-inspired naming system for the Khazad. I wasn't aware that there was a canonical name for the Luchuirps' empire already - "Kradh" is fairly similar to "Khaz" anyway, you can imagine the slight linguistic shift when the races separated resulting in that; the more traditional Khazad retaining their old word as the innovative Luchuirp progressed, allowing their language to evolve and change. One thing I overlooked when considering the name of their nation was that it could already be right there: Khaz Ad. The word "Ad" seems to be one of those words that doesn't change much over time, even many thousands of years - words like sister, brother, person, etc. (e.g. *aner- -> anēr -> ándras, following the PIE -> Ancient Greek -> Modern Greek evolution of the word for "man"). Perhaps "ad" and "ak" are forms of the same word, a word the Khazad used in ancient times to refer to themselves, which has since been replaced with a word that describes them in relation to their nation - i.e. at first they were the "ad", then they named their city "Khaz Ak" meaning "city/place/home of the ad" or somesuch, then "Khaz Ak" came to apply to the empire which grew out of that city, eventually changing to "Khazak", and the Khazad adopted the "Khaz" from the name of their country - or foreigners did when they encountered them. Does that make any sense? Alternatively, perhaps "Ad/ak" are forms of a word meaning "under" or "beneath", words very important to those who live beneath the surface, and "Khaz Ak" means "underhome", the word for "home" (khaz) also meaning a person, or a dweller, therefore "khaz ak" means both "underhome" and "underdweller". Or maybe Dwarven grammar has a case that describes something as being inside something, and their grammar works oddly, so "khaz" means under, "ak" means home, and "ad" means "something in a home". I'm rambling so terribly...
It baffles me how "Luchuirp" can be related to "Kradh-ke-zun". I'll just assume that it's not and let it pass... Oh, who am I kidding, no I won't. Perhaps "luchuirp" is a word they used to describe themselves after adopting their lifestyle as artisans and craftsmen on the surface, meaning just that - "artisans" or "craftsmen"; while "Kradh-ke-zun" means "Home-above-surface" or somesuch. That would suggest "Khaz" means "home", also.
With Illia, I was thinking not just about the obvious "Illian, American, Illia, America" thing, but also about Troy. It's said that the Illians once had a great empire, isn't it? Perhaps in the same way that Troy, once a great and beautiful city, was laid waste to by the Greeks against very great odds; Illia was destroyed by the Amurites. Though the parallels really stop there - the Illians are clearly evil, while obviously in "real" (or at least only semi-fictional) wars, there aren't really good and evil sides.
Kuriotanea might work for the Kuriotates - close to Greek "Kyrionea", but removed. What would be really interesting and time consuming would be to write the languages of Erebus, alphabets and all.
The singular of Hippus is Hippy? Crazy. I always wondered why they always seem to go for FoL (or OO...). Maybe all their grammar is back-to-front Latin, and their land is "Hippi" as well. Though that sounds a little bit silly/Finnish.
Emberlands might be nice for the Clan. I suspect they'd mostly be referred to with derogatory terms by the civilised world, however, and their name for themselves is probably unpronouncable.
