Thank you all for the critique so far.
>Grave
Hmm, what if I make it that the default Burrow Speed is either slower or loose soil only until, say, level 5 or 7? Then it boosts back up?
Maybe Necrotic Resistance would be appropriate? 3e's Grave Elementals didn't really take advantage of the "necromantically infused earth elemental" thing that much, but new edition is a chance to rewrite lame monsters, and it makes sense that an elemental of earth-with-corpses-in-it would have necromancy affiliations, yes?
>Pyre
Okay, you don't need to twist my arm, I get that the amount of damage Burn With Me was doing is overpowered. ;p But, doesn't it kind of stink that you can't use your nature as an embodiment of fire's destructive, death-dealing aspect unless you're bare-handed, and so sub-optimal? Maybe there's a way to add some bonus Fire damage to weapons that isn't so broken?
>Mist
Yeah, they were kind of the race I had the most problems with. They're pretty damn lame even in 3.5 - Obscuring Cloud 1/day, enemies have lower concealment from mist, and the standard elemental protection. Stealing from the Wood Elf might be one thing, but any other suggestions to buff them up?
>Blood
Yeah, Bloodscent is one of the traits they had in 3.5 that I don't know if it can pull off in 5e. Maybe Advantage on Wisdom (Perception) checks made to find creatures that are injured or otherwise bloody?
Maybe make Thief of Life similar to Burn With Me and instead make it a not-overpowering amount of bonus Necrotic damage with each attack? Vampiric Touch at 5th level alone is kind of similar to the current problem with the Mist Genasi, isn't it?
>All
Actually, do you think that by the fluff, all of the Dread Elemental Genasi should maybe have Necrotic Resistance? Necrotic is the new Negative Energy, so it's kind of the death/evil element in the game, isn't it?