Zardnaar
Legend
I never considered Dark Sun to be low magic. Gritty? Certainly. The entire setting was out to kill you in horrible ways, but even the most bestial of opponents had magic tricks, sorry psionic wild talents. Athas always felt equal parts John Carter and Conan with a little super hero thrown in. Dark Sun was over the top. Ability scores went to 21. You started at 3rd level and had super powers, sorry wild talents again. Wizards could level as fast as rogues if they merely turned the world a little more ashy. I loved it.
5e seems a good fit for Dark Sun but needs some serious fluff adjustment. Without the addition of psionic classes and wild talents, the base classes are going to have to fill in. Paladins and Hexblades make good fill ins for Psychic Warriors Bards can make ok psions maybe a new oath for paladins Oath of Fealty to the Sorcerer King?
Giving the variant human free feat or asi at first unless a large race is pretty elegant actually. Thrikreen and Half giants will not over shadow and it echoes the advanced starting level of 2e Dark Sun
I tweaked the default human for darksun. The extra feat thing is also for elves Dwarves etc got the idea from groups that grant a bonus as I level 1 anyway.