I mean in lore, cultural and appearance aspects. So no mechanics.

Lizardfolk, yuan-ti, and firbolgs for me.

Leonin. When I was a child I was obsessed with scientific information about big cats, so playing a lion-person appealed to me. Additionally, their attitude towards the gods of Theros speaks to me.

I like high elves. They exude that better-than-thou attitude and have what it takes to back it up. Elves in general also live longer and have better long term planning.

I like goblins.

They occupy a place in the world as the default threat to nearly any town, and have a bad reputation for cruelty, spite and violence…

…so I like the challenge of making a goblin who isn’t necessarily that, but has to deal with those preconceptions.

It involves a lot of hoods, disguises or magic to smooth things over.

I also like aasimar…specifically the bit where evil creatures tend to seek them out to try and kill them.

It makes for an interesting personal conflict…they have to keep moving, or risk evil monsters endangering those around them.

They might grow to hate their heritage. They might embrace it.

Halflings would make my third favorite…I like their outlook. I like their luck, and how they are compelled to adventure every now and then, and bring back trinkets or objects from their travels, if for nothing else to instigate a good story to tell.

Warforged, hands down.

Dwarves. I will never get bored of the idea of them living in mountain citadels and having to reclaim ancestral treasures for whatever reason. I could hear that story forever and a day and it would be just as fantastical. There isn't a version of Dwarves I've been bored of so far, though I would like them to finally decide whether they're all Scottish or Yorkshiremen. I suppose that's one of the age-old conflicts that we'll never see the end of.

I find most of them very interesting, the only ones I don't get on with are Elves and Half Elves. I struggle to get behind their way of thinking and their characters. Probably because most media has Elves as being uncaring or cold, when I am anything but. I may make another effort with them, perhaps styled more after the prince from Hellboy 2 (which, despite false claims, was the last Hellboy movie).

Lizardfolk, for being pragmatic, capable survivalists who snack on their dead enemies’ crunchy digits when they feel peckish.

Hobgoblins, because death before dishonor.

Shifters, since they’re the quintessential adventurers, self-reliant but also great friends, always prepared boyscouts of D&D.

Quote from ThorukDuckSlayer >>

I find most of them very interesting, the only ones I don't get on with are Elves and Half Elves. I struggle to get behind their way of thinking and their characters. Probably because most media has Elves as being uncaring or cold, when I am anything but. I may make another effort with them, perhaps styled more after the prince from Hellboy 2 (which, despite false claims, was the last Hellboy movie).

 The stereotypical “cold, stoic & smugly superior” type of elf is what I attribute to the Sun Elves.

Apparently, the “High Elves” are split into two loose subcultures…Sun Elves & Moon Elves.

Sun Elves are your militant, refined, and traditional grouping where popular media can be lumped into with.

Moon Elves, when I read about them, changed my mind about D&D elves…Moon Elves are sweet!

Rockstars, artists, performers…and they actually like hanging around with the other mortal races.

It’s like they’re an entire sub-race of bards.

Dwarves and Goblins

In video games, gnomes or the shortest race possible. Every time.

Sometimes it depends on the setting.  I'm generally partial to humans, dwarves, half-elves, half-orcs, warforged, and goblins.

Warforged

Obviously, androids are cool. But I also like the backstory that they have recently gained sentience and are looking for their purpose in the world. Plus, there is the possibility to homebrew "upgrades".

Aarakocra

There are so many kinds of birds. You don't always have to play an eagle or a hawk. Different birds have different personalities. How about a peacock? A hummingbird? A swan.

Dragonborn

Dragons have a vibe of stoic dignity. A good choice for intimidating "big guy" builds if you don't want to go with the more mainstream half-orc. Both look like they would mess you up if you piss them off. But dragonborns seem like they have full control over their emotions and will only deal out that beat down if you don't give them any other choice, whereas half-orcs are hoping you say the wrong thing.

Tabaxi

Cats are iconic. Not only are they known for their uncanny balance and dexterity, they also have diverse catty personalities. Different strokes for different kitties. Some are aloof and fierce if you invade their personal space. Some are manipulatively seductive. Some are curious and easily distractable.

Quote from BogWitchKris >>

Someone in my group posted a quote from elsewhere: "go to your local dnd night, make friends with whoever plays a tiefling because those people are definitely gay." Obviously lots of people who play tieflings aren't gay (or LGBTQ+), but I can say that a large part of what appeals to me about the race is how tieflings are stuck with this association with devils through no fault of their own based on some ancient concept of sin. There is a stigma and antipathy toward being a tiefling that can lead to being discriminated against despite the fact that you may not be a bad person. Does a tiefling come to learn shame for what they are, or do they learn to embrace it as their own sort of beauty despite knowing what many people see is a devil?

There is something very familiar about the race, and playing it when you can be a bad ass mf'er who doesn't have to take any crap from Nameless Villager no. 42 is... cathartic.

 One of the "good guys" offered the tiefling in my party what amounts to "conversion therapy", and my character was like, "Yeah, nah. If you can't get accepted in human society, you can **** off to my druid grove where we accept all kinds."

Elves and Dwarves. They’re classic, and as a result they’re the most distinct, diverse, and well-developed. I’d put Halflings in that box too, but “cool” isn’t really a word that applies to them!

Warforged, because I glossed over the Eberron 5e book recently and the way they sort of 'adopt' a new life after their purpose of being a fighting robot was no longer required just seems cool to me.

Drow in second place. I roleplayed them a fair bit back in the day and it was just cool dealing with politics at a table of other noble houses.

I think that Elves of any variant are the coolest race in my opinion.

High Elves, half-Elves, The Drow...and all Elves in between. I like their use of magic. I think they have the most wisdom and intelligence. 

Tieflings are HAWT.  'nuff said :)

Quote from Golaryn >>

Tieflings are HAWT.  'nuff said :)

 Yours certainly is. Green and pink is a good combo.

Coolest, or the race that I like the most? If it's strictly coolest, it's Warforged, no contest. If it's the race that I think makes the best characters (and that I enjoy the most), it's gnomes. Yes, they're weird and eccentric, but that's precisely why you play a gnome! I mean, just check out all the Clockworks that they can make to serve them! And Autognomes!