I've been reimagining my original four Genasi. All four could be one kind of Druid or another, as Druids do have a lot of Elemental abilities, but I thought I'd try to make them using other classes.
Terrus was always more of a Fighter. He would probably be a Rune Knight Fighter. They can grow large, and have a little magic, and can do the whole Two Handed Weapon thing. He could also be the new Psychic Warrior subclass from the UA a few months ago. Probably more of a Rune Knight, though.
Pyrus was the castor of the group. He would likely be either a Wizard or Sorcerer, focusing on Fire, of course. Evocation Wizard or Draconic Sorcerer. Stats would work better for the Wizard, but Sorcerer works better for the RP.
Auraia was of the winds, and more of a Striker, so she would likely be a Rogue. Probably an Assassin, though the new Soul Knife is a Rogue subclass.
Aquaria would be a Druid, I think. She'd focus on Water magic and healing.
It would be interesting redesigning them and running them in a game some day.