Henadic Theologian
Legend
I'd like it if they did Treefolk.
Noggles I can see being handles by reprinting Goblins, again, with some fresh lore.
I don't think they are going to reprint Goblins, if they do a Gobliniod species in it, I think it will be Boggarts as a more magically Gobliniod species.
Treefolks again might be too big, unless they do Shrubfolk or Bushfolk.
So they book will cover 10 fey themed species, 2 of which will be new.
1. Rimekin we know about.
2. Mystery new species my guess Kithkin
3. Guesses for the 8 preexisting species with advise starts here: Gobins
4. Elves
5. Dwarves/Duergar
6. Changelings
7. Fairies
8. Goliaths as small giants?
9. Tritons as Merrow who have two legs somehow?
10. I could be wrong about Kithkin or it could be Hexborn (Hags).
Other payable Fey like Centuars and Satyrs don't appear in Lorwyn sets in MtG, although who knows this is Domain of Delight Lowyn, it likely has a different history like no Phyrexian invasion.