A Few Potential Elf Sub-Races

So, in preparing for a campaign (my first homebrewed one) I was trying to get a feel for the shape of the world and the history. In that process I had an "age" or long period noted by Elven dominance with a series of city states. Figuring that Elves themselves are naturally adaptable and respond magically to their environment, I thought it'd be good to flavor some sub-races to line up with some potential city states. The ones that aren't covered by the PHB are a desert city, a floating mid-ocean city, a city in the caldera/side of a volcano, and/or a city in the arctic north/south.

tldr: Elf sub-races to match environment of cities they live in (Sand, Ocean, Volcanic, Arctic).

Anyway, on to the sketched ideas.

Sand Elves (Desert City)

  • +1 Bonus to Constitution
  • Proficiency in Survival
  • Can cast Blur as a second level spell once per long rest.
  • At third level can cast Misty Step once per long rest as well
  • Weapon Proficiency in the Scimitar, Shortbow, Pike, and Dagger (possibly Spear)

Ocean Elves (Atlantis)

  • +1 Bonus to Strength
  • Can breathe in both air and water
  • Can cast the Shape Water cantrip at will
  • Weapon Proficiency with the Trident, Quarterstaff, Rapier, Longsword, and Longbow

Volcanic Elves (Literal Volcano)

  • +1 bonus to Intelligence
  • Proficient in Arcana
  • Can cast the Firebolt Cantrip at will
  • Can cast Flame Blade at 2nd level once per short rest (should ever get the level to increase the spell level?)
  • Weapon Proficiency in the Greatsword, Longsword, Shortsword, Longbow, Shortbow (Perhaps flavor it into more Battleaxes instead of blades?)

Ice Elves (Arctic Cities)

  • +1 bonus to Wisdom
  • Can cast Ray of Frost and Frostbite cantrips at will
  • Once per long rest, can cast Ice knife as a 1st level spell
  • At seventh level, can cast Snilloc's Snowball Swarm once per long rest.
  • Weapon Proficiency in the Glaive, Longbow, Shortbow, Rapier, and Longsword

I am mostly looking for advice on the last two, since they have a number of spells that I dont know the limits of. I understand that things might need to be tweaked and some things removed, but I wanted all the ideas out on the sheet. Honestly most attached to the Sand Elves as a concept, even if it requires a complete alteration of what I have there, and the Flame Blade of the Volcanic Elves. Even if I set the campaign in a different age/era, encountering and exploring these ruins and cities, perhaps encountering a wandering vagrant leftover of them or something.