D&D 5E [5e] Arcane Trickster optimization and questions

[Poeta]

Hello.
A couple days from now, i will be playing my first 5e game.

I decided to roll a Arcane Trickster, as i love the concept and it fills two roles the party needs. The group is pretty optimized, so i want to make sure i'm up to par.

High Elf Rogue, Arcane Trickster.
Sage background.
Skills: Acrobatics, Sleight of Hand, Stealth, Arcana, History, Investigation and Perception.
Cantrips: Booming Blade, Green Flame Blade, Mage Hand and ????

STR: 10 DEX: 16 CON: 14 INT: 16 WIS: 10 CHA: 8

So, questions:

Am i missing out if i don't Multiclass?

Is my ability spread OK? I'm not sure if i should or can afford to go 8 STR to up CHA to 10.

What my fourth cantrips should be?

Besides mobility, any other feat i should consider?

Does Green Flame Blade and Booming Blade work with Sneak Attacks?

 

[faria]

CHR will come up more than STR. Persuasion is useful. Deception for a Rogue. 9x out of 10 you can roll your Acrobatics instead of Athletics checks. Just tell the DM you wanna do it with flair.

 

[Z. H. Darkstar]

How did you derive your stats? Was it via rolling or point-buy? Remember that Half-elf comes with +2 Cha, so the lowest that a point-buy Half-elf can have their Cha is 10.

Faria, the PHB has rules that allow skill checks that use different ability scores. You're more likely to convince a DM that you should be able to make a Dex(Athletics) check for certain situations than to wholesale swap out Acrobatics for Athletics. I'd still keep Athletics proficiency and make the arguments for a Dex(Athletics) check when applicable.

 

[Poeta]

How did you derive your stats? Was it via rolling or point-buy? Remember that Half-elf comes with +2 Cha, so the lowest that a point-buy Half-elf can have their Cha is 10.

Faria, the PHB has rules that allow skill checks that use different ability scores. You're more likely to convince a DM that you should be able to make a Dex(Athletics) check for certain situations than to wholesale swap out Acrobatics for Athletics. I'd still keep Athletics proficiency and make the arguments for a Dex(Athletics) check when applicable.

Point Buy.
And it's high Elf.

 

[Z. H. Darkstar]

Point Buy.
And it's high Elf.

This is what happens when I rely on Passive Perception...

Do you foresee yourself making lots of History checks in your game? The PHB has rules for customizing backgrounds. See if your DM will allow you to swap History for Investigation, so you can take Athletics with your Rogue proficiencies. Even if your DM won't allow for Dex(Athletics) checks, being able to shore up your grappling defenses is a boon to a Rogue. I'd even consider making it one of your Expertise skills.

BTW, what's the rest of the party composition? Seeing that will better help us tailor your AT into filling the missing pieces of the puzzle.

Edit: GFB/BB will work with Sneak Attack. I've got a VHuman Battlemaster/Swashbuckler build that takes advantage of that.

 

[Poeta]

This is what happens when I rely on Passive Perception...

Do you foresee yourself making lots of History checks in your game? The PHB has rules for customizing backgrounds. See if your DM will allow you to swap History for Investigation, so you can take Athletics with your Rogue proficiencies. Even if your DM won't allow for Dex(Athletics) checks, being able to shore up your grappling defenses is a boon to a Rogue. I'd even consider making it one of your Expertise skills.

BTW, what's the rest of the party composition? Seeing that will better help us tailor your AT into filling the missing pieces of the puzzle.

Haha, no problem.
Yeah, i can see History coming up quite a lot because it's a original setting, so the DM may want to do quite a bit of exposition.

And no, creating a background is not a option.

My party is a Paladin, a Monk, a Bard and a homebrew Arcane Archer ( Warrior and Wizard Multiclass )
But the Arcane Archer may end up playing a Ranger.

 

[Z. H. Darkstar]

With that line-up, you have two CHA-focused characters who should be doing the lion's share of the Persuasion checks. Therefore, dumping CHA isn't a bad thing. Stats look fine as they are.

Fourth cantrip? That's an easy one. Message. Super useful when scouting ahead.

Mobile is a decent feat, but Cunning Action takes the wind out of the sails of the pseudo-Disengage that Mobile provides. Take it only if you think you need the speed boost. Resilient (Con) is a better choice, as it helps with maintaining concentration on your spells. War Caster might even edge out Resilient, as you can pop off BB as an opportunity attack.

Edit: If you do feel the urge to multiclass, going 2 levels into Wizard to be a Bladesinger will up your combat defenses, give you access to 1st-level rituals and a few more cantrips, slightly speed up your slot progression, and give you back one 1st-level spell slot at the end of a short rest once per long rest. All of this at the cost of 1d6 SA and the last two levels of Rogue abilities.

 

[Poeta]

With that line-up, you have two CHA-focused characters who should be doing the lion's share of the Persuasion checks. Therefore, dumping CHA isn't a bad thing. Stats look fine as they are.

Fourth cantrip? That's an easy one. Message. Super useful when scouting ahead.

Mobile is a decent feat, but Cunning Action takes the wind out of the sails of the pseudo-Disengage that Mobile provides. Take it only if you think you need the speed boost. Resilient (Con) is a better choice, as it helps with maintaining concentration on your spells. War Caster might even edge out Resilient, as you can pop off BB as an opportunity attack.

Message may be useful, you're right.
About mobility, i considered it because if i could hit and run without spending my a bonus action, i could use it to generate Sneak Attacks pretty much every turn with that Mage Hand ability.

 

[Z. H. Darkstar]

Btw, check the edits on my last two posts, as I added some things to them that you might have missed while replying.

 

[Poeta]

I saw the edits.
I guess my passive perception is quite good.
But thank you.