I am glad there is only one kind of
Human.
I wish there is only
one kind of
Elf.
If the Elf traits are only:
• Fey Ancestry
• Trance
• Innate Spellcasting.
Then this simple description can represent each and every of the over hundred kinds of Elf in the history of D&D.
The Innate Spellcasting feature grants a choice of two cantrips, a slot 1 spell and a slot 2 spell. A cantrip can be Darkvision or Waterbreathing.
Done.
Then different Elf cultures can value and encourage different choices of spells.
Drow is a culture, not a subspecies. High is a culture, not subspecies. Even Sea is a culture, not a subspecies.