RJ succeeded with making the Aelfinn and Eelfinn something other than merely "people in funny suits" which bugs me about the likes of the Dragons of [Autumn/Winter/Spring] trilogy and other series in that wider series, and other fantasy novels. A lot of those sorts of elfin creatures are taken from Tolkien without the writer taking the trouble to find out the behaviour of the elfish/trollish creatures in the myths Tolkien used for his fantasy, which, as I say, they wind up being "people in funny suits". I'm afraid I don't care for "people in funny suits" - once when I was a kid, in the Papua New Guinean bush, and going through some section of the bush that the locals didn't use, I was told by a local who saw me, "Bai masalai i kaikaiim yu!" - the local woodland spirit will eat you! And that guides my reading of everything that involves woodland spirits, house spirits, water spirits, and the like. Of course, Tolkien "baptized" the woodland spirits and made them into "natural Catholics" - it's good that RJ "unbaptized" them, so they are closer to their original style, but the problem I find is that they're "semi-technocrats".
I would recommend reading https://www.oocities.org/thslone/masalai.html
and likewise
https://www.amazon.com/One-Thousand-Papua-Guinean-Nights/dp/0971412715