Praise Lolth,
While I believe Drow to be the superior of all dark elven races there are so many more. Elderscrolls/skyrim etc. Elves are already split into sub categories as it is in this world so I don't know if they will quickly add in another faction of elf period. There are no Half elveswhich also lead me to believe that there is no cross breeding amongst the races either. I think the best we could hope for is a necromantic elf in this world.
I certainly would not mind at all however if there was at least one spider worshiping dark elf race teleported in from another place......*crosses fingers*