Void elf has the best armor resolution IMO because the rest of the alliance races have wonky proportions. The heritage chest is also really good looking for dk.
Female NE is a solid option and having a way to drop combat on DK is a huge QoL increase for world questing. Plus the night warrior eye option looks amazing with dk pestilence themed mogs. Male NE shoulders go brrr.
Lightforged Draenei have really weak racials, like maybe the worst in the game. You’d probably be better of with a standard Draenei, especially if you’re a blood deathknight for the gift of the naru self heal, it has no GC so just macro it to one of your abilities for a free regen whenever its off cooldown.
Void elf is a and odd one, because they do have mobility options which is something deathknights lack. And you could combine the voidelf blink with deathgrip to pull things into a location of your chosing, could be interesting. Entropic embrace is also just an overall solid racial too, just remember to stall on your high burst abilities for when it procs to make the most of that 5% damage boost.
Pandaren… meh… I honestly don’t care for them, they look like a joke to me. A goofy, not funny joke. Also Quaking palm is going to be pretty usless on a deathknight as you’re DoTs will break the CC almost instantly. You may get some decent mileage out of the well fed boost though.
Human, is just solid really, you can’t really go wrong with a human they are well rounded with usefull racials and suit most aesthetic looks… they are however, pretty bland, and since you allready have one that dosen’t help
Void elf has racials that mesh perfectly with Death Knights.
LFD makes no logical sense but if you like it go for it.
If you like Pandaren, go for it.
My pick is Human myself.
If looks are your concern, consider this (if someone could post picture, I’d appreciate it): https://wow.zamimg.com/modelviewer/live/webthumbs/outfit/105/444777.webp
Here’s the WowHead Dressing Room Link: https://www.wowhead.com/dressing-room#fg80o0zb89c8Vs81v8VR81n8Va81F8Vq81U8ba8Mus8Vb8208qU8Mwp8ft8mvb8fH8M5k8fZ8M4q8wC8mB08wh8mER8wn8mlm877hUZU808SRq808zMoM87k2rw8082ru8082ri8082rf8081vs87s
Anywya on topic. Pandaren have great animations, Humans are the “traditional choice” but personally I am a big fan of the Worgen dk. I do agree Draenei in general look Great in heavy armor however.