I feel like I'm going to regret asking this, but

Ask your players what they want to play.
The races they pick are then the main races of the setting.

The base races...?

No Dragonborn though, you'd have to drown the poor fuck who chooses it in Dragonrific Lore that goes on for hours and hours till boredom hits.

Sounds like what you're really asking is: How do I introduce the races to my players who are casuals?

Which is

Halfling:
Say hobbits but they're not midgets because they look good, and vary from comfy people who leave their doors unlocked at night and welcome guests to thieving little street urchins/travelling gypsies

Dwarf:
You don't have to tell them shit.

Elf:
Give them the choice of the High ones, and the wood ones because they're casuals, no Dark elves though, tell them the dark elves here earned that title for a reason

Humans: Normal and Higher, because We need Ubermensch.

And a mandatory unconventional party mascot race of choice: Tie this character to the two friends in the group who are closer than most in a bromance relationship or some shit, no homo I.E Kobold.

Limit the wizard to generalist, and the cleric to most of the good deities, try to dissuade them from worshiping YHWH tier mopheads if possible, wargods may be a good idea.

If anyone wants to play a half-orc, they have to make him dumb. at least.

Party should consist of:
Fighter
Wizard
Thief/Bard?
Cleric

Thief needs to be jack of all trades, the Cleric is supporting the fighter because Wargod and because Fighter's probably getting casualties the most, and the Wizard is support until he's the appropriate level to get smart with everything.

Fighter is Just smash all the time.

just Dorfs

So far the four players (after telling them we're only using phb for playable races) want to be:
Human
Human
Dwarf
Tiefling

God bless my group, could have been a lot worse lol

Pretty tight knit, I don't expect racial tensions or anything, two humans, a Dwarf for reinforcement of sense of honour, pride, and the drinking buddy, and a Tiefling for the Extraplanar flare.

Don't use 5e.

If you have to, just let them use whatever from the PHB, ASIDE FROM VARIANT HUMAN.

Seriously, don't let them use variant human.

Well depends on what kind of game you're running my dude.

if you wanna be tolkienesque and generic just allowe the normie races (elv, dorf, halfin, hiumin maybe hafok and nomes)

if you aim for high magic maybe even magicpunk or some sort of planehoping adventure i'd say include all, the more outlandish the better

and if your idea was something more along the lines of gritty gameofthroenesy ""realism"" i'd say stick to humans only, maybe have other races only as misterious monster npc antagonists

If they are new players you may just want to have one race. Start them off as dwarves from a dwarf village, humans from a human town, or maybe wood elves from a forest city. Whatever.

When someone dies they can make a new character of whatever race they like that would fit otherwise.

Other than that, the real question is what races make sense for your campaign.

I like Variant. The Human feels bland and a little underpowered without it. If you go to Adventurers League, you'll see almost no one play as a human, whereas in my personal games I've seen it chosen about half the time, which feels more accurate to most settings where Humands are more common.

A lot of people will argue that it's a Powergamer's option, but really I've seen it more used as a method of personalizing one's human character.

Also, most people on here who argue against also argue against the use of feats as a whole.

The fact remains that variant human is enabling for powergaming optimisation. If you trust your players, let them go with it though.

Out of curiosity, what sort of races & classes do you typically see people bring to the table for AL?

Variant human's problem is that the bonus feat is very powerful at level 1. Homebrew it so that variant human only gives out the bonus feat at level 4 and you'll see that they're actually pretty balanced.

No matter what, re-read the Fell's Five comic before DMing.
It's magical, and gives a couple dice worth of inspiration to the DM himself.

Well
>you shouldn't start play at lvl 1 but around lvl 3 anyway
>other features like darkvision are at least as powerful - do you like getting extra turns in combat? then you need to stealth, can't stealth with a fucking torch

Stealth is worthless unless your whole party is good at it.

Well yeah. Have fun playing a rogue without darkvision. The meatwall paladin can get away with casting Light on his shield, you sure as hell can't get away with a torch or lantern. Variant human might even turn out to be a bit weak, I expect a big part of its overabundance is because a lot of people like playing humans and variant is versatile enough that pretty much all classes will do well on it.
For instance, half-elf is way overused at my table because we all like being diplomancers, we all tend towards rogues or bards, and we all want to have darkvision.
If it were up to me, darkvision would just be a monster ability. Let players use magic to replicate it, or carry around lanterns, torches, pebbles enchanted with light, even candles. In the end it's up to the DM to light the dungeons, even someone with darkvision isn't going to want to live in dim light all the time. Dungeons will have light even when they're inhabited by darkvision monsters. Dragon lair? Maybe not a lot of light, but by the time the fight with the dragon starts, maybe he starts some fires and the room becomes illuminated?

Everybody is always good at stealth if the dm leaves 'normal' magic items around, the elven cloaks are fucking op this time.
Getting the drop on someone is a problem only when it's operators operating agains other op operators.