Arcane trickster optimization help please:

I’m stuck on racial choice.

Lightfoot halfling guarantees me a hiding spot, even if it’s behind a teammates cloak. Rogues only get one attack, halflings reroll those critical fails.

Forest gnome gives me optimal stats (+DEX/INT), an extra cantrip, and awesome saving throw bonuses.

High elf gives me optimal stats (+DEX/INT), an extra cantrip, a better ranged weapon option, and elven accuracy, which is a great ability for a rogue.

Half elf could be an option as well, giving me more skills to choose from, as well as the option to take elven accuracy, which seems amazing in paper.

I’m open to other options, and I’m not a fan of custom lineage. Switching stats as per Tasha’s is NOT an option.

TIA.

Edit: we used rolled stats. Mine are a little bit better than the standard array, but they’re not spectacular. Here are my options:

Halfling: 11/17/14/14/12/12
Gnome: 11/16/14/16/12/11
Elf: 11/17/14/15/12/11 (elven accuracy would be my choice at 4th)
Half elf: 11/16/14/15/11/14 (I’d probably invest in deception here as one of the skills, as well as elven accuracy feat at 4)

It’s a Curse of Strahd campaign, if that matters.

Several things to consider here.

1) Move speed. Those shorter races have their advantages, but the more you give Cunning Action, the more it gives you back. The 5ft additional speed the Elf gets by comparison is doubled to 10ft every time you use CA to Bonus Action: Dash. Wood Elf, which also benefits from additional hiding options in natural terrain (like fog and forests *cough* Curse of Strahd *cough*), gets 10ft additional movement compared to the small-folk, doubled to 20ft with CA:Dash. If you Dash again, that discrepancy grows again. In real numbers, a Halfling/Gnome has 50ft speed compared to the High/Wood Elf 60/70ft with a single Dash, or 75ft vs. 90/105ft with a double Dash. Unlike campaigns that occur largely in smaller spaces like indoors or underground, CoS does make use of a fair amount of outdoor and large spaces where that increased speed might be significant.

2) Ability Scores. As far as I can tell, your Elf and Gnome arrays don't have to be different (i.e. they could both enjoy a +3 modifier on both Int and Dex). Worth considering. Also, Wisdom might stand you in better stead than Con. I appreciate the difference is minor, but Arcane Tricksters have some of the best defences in the game when it comes to physical damage, but you won't really be looking at any bonus to your mental defences until the late game (which in CoS might never happen). That said, Gnome does gain that significant advantage vs. spells. With that in mind, I would consider Wis 14 on the Elf, if not also the Gnome.

3) Darkvision. Halflings don't get it. Dancing Lights offers up to an effective range of 60ft bright light and a further 60ft dim light in a 20ft wide corridor to a character with standard Darkvision without recourse to lanterns (those with 120ft Darkvision, such as Drow or Svirfneblin, have 80ft of bright light, near or far from them, plus the additional 40ft dim). Perception checks are at disadvantage in dim light.

4) Svirfneblin (Deep Gnome) enjoys optimal Ability Score bonuses (+2 Int/+1 Dex) if you want to stick to the OG Elemental Evil version, as well as having that increased Darkvision range (without the light sensitivity of the Drow) and the bonus to stealth checks in rocky terrain doesn't hurt either. That's on top of the expected Gnomish bonus to saves vs spells. If you prefer, the Mords MoM version also has 30ft speed, Disguise Self and Nondetection as bonus spells and expanded utility on that Stealth bonus (no longer limited to rocky terrain, but only prof bonus times per long rest). Either way, you also get access to the Svirfneblin Magic feat, which gives you Blindness/Deafness, Blur and (another use of) Disguise Self as well as de facto 24/7 Nondetection (no material component cost). As a Gnome, they also get access to the Fade Away feat, which is a one-round invisibility, once per short rest, conditional on taking damage (making it a good defence against multiple attacks/attackers; something Rogues tend to be weaker against than some others in melee). All of which is great for any Rogue, but particularly one participating in a campaign that notoriously features spellcasting enemies that enjoy deceptions and treachery over direct conflict, as well as some solid options for additional spells known as an Arcane Trickster.

I wouldn't put too much weight on movement speed, for a rogue. Sure, the difference in speed will be multiplied by Cunning Action, but even for a 25' base, 50 feet of movement (or 75 with double-dash) is generally enough (especially considering that most of your party-mates will be limited to 30, or 60 with single-dash).

The halfling lack of darkvision, however, is a nuisance. You can get around that a little if you have a familiar (preferably a bat), to use its senses, but that takes your action, so you'll still need some sort of light source to actually do anything beyond just scouting. Then again, you're likely to have at least one party-mate who also needs a light source, and going off away from the rest of the party isn't really an option for 5th edition rogues.

Between the gnome and the elf, the main advantage to the elf isn't anything the race itself has, just the option to take a feat. And there are plenty of other things you might want to spend that feat on. Three-dice advantage isn't actually all that much of an improvement over two-dice advantage, either, unless you're crit-fishing. Longbow proficiency doesn't matter much, because a longbow has very little benefit over a crossbow, without extra attack. I suppose the elf also has free choice on their cantrip, too, but Minor Illusion is good enough that it's likely to be one of your cantrip choices anyway.

It’s rarely helpful to add more options when trying to pick but if it’s allowed I’d toss autognome on that pile.

Being able to mending yourself, built in armor, free bless rolls, and all the perks of not being alive.

Still has that dark vision issue though. It’s banned at a lot of tables though for theme reasons so maybe yours too.