Flawlessness

[SweetScreams]

Sweet Screams Frankie.
She's got Bonita hair, and the best design ever.

I agree! She's just splendid. Also all the Circus dolls. Just.Wow.

I totally fell in love with Music Festival Abbey. Her soft and manageble hair and awesome boots just got me!

[Portobella]

There aren't many I find flawless, but I think G&B Venus and EAH TTW Ashlynn are perfect just as they are.

[Pyrefly Projects]

There aren't many I consider -flawless- right out of the box, because I love to tweak them and redress them, and also try to limit myself to 1 doll per character. But having said that, looking in my display cabinet I have these girls, exactly as they came -

Wave 2 Frankie - My first MH doll
Most of the DotD line.. They're just so classic and clean.
Field Trip Gigi
Freak du Chic Twyla - Perfection
Signature Rochelle
EAH Mira Shards

Dolls that come close -
The Gloom & Bloom ladies, Venus especially. I have Zombie Shake Venus wearing it, but that outfit is IMO the best thing Mattel will ever make.
I Fashion - Clawdeen, Frankie, Abbey, Wydowna and Iris - I only list these here because obviously they don't wear -everything- they came with
EAH Dragon Games - Just because some of the armour needs details painted IMO

[furyXIV]

Spring Unsprung Holly, which is weird cause normally I'm not a fan of Holly's dolls. For Monster High Sig Honey Swamp and maybe Kala.

[Megaame]

School's Out Cleo. I absolutely adore her. She's by far my favorite Cleo doll and probably my favorite MH doll. I love her hair the most. The angled bangs and the hairband around her head look amazing together.

[LightningBolt]

Flawless dolls to me?

I'd have to say FCA Elissabat (not her tall doll, as her flat bangs are a minus) Little Dead Riding Wolf, 13 Wishes Howleen, Ghouls Rule Draculaura, Signature Toralei, SDCC Valentine, and I Fashion Venus are all perfect in their own ways.
Truthfully, I liked all of them from first glance, and I wouldn't change a thing on any of them. Definitely my favorite versions of each of those characters too. Well, those that have more than one at least!

[ngcskate]

Since my collection is primarily Ghoulia, I would have to say the flawless beauties are SDCC Ghoulia - she is beyond gorgeous.  Gloom Beach Ghoulia is also stunning.  I would put original Ghoulia in third - she's also perfect just the way she is.

As a line of dolls, which I don't buy as a rule, Freak du Chic is the best line ever.  Every doll is perfect, the details are amazing and they all tie in to each other in the most awesome way.

[Ocean]

I want to add Lagoonafire and Clawvenus and give a "hear hear!" for Dead Riding Wolf.

[Shenanigans]

There's so many that I think are flawless! Let's see...

MH:
Ghouls Rule Abbey
13 Wishes Clawdeen
BYBY Cleo
Sweet 1600 Frankie (possibly my absolute favorite MH doll)
Ghouls Rule Frankie
Freaky Fusion Recharge Chamber Frankie (this doll is just amazing)
Skull Shores Frankie (B&W and color version. I normally don't like short hair on dolls, but Frankie looks amazing!)
Picture Day Lagoona (I bought her just to get free shipping on my Toys R Us order, but holy cow she's amazing! I was surprised I loved everything about her!)
WTMH Dance the Fright Away Lagoona (my very favorite Lagoona, I love her new face)
Dot Dead Gorgeous Operetta
Haunted Rochelle
Love in Scaris Rochelle
Freaky Field Trip Toralei (I know she's simple, but I adore everything about her! I especially love the teal streak in her hair)
WTMH Photo Booth Draculara (I think I love her so much because the heart over her eye reminds me of EAH Lizzie Hearts )
Ghouls Beast Pet Draculaura (love the blue heart on her cheek)

ALMOST flawless:
Fierce Rockers Catty (wish her shoes were pink)
Scarily Ever After Clawdeen (I don't care for her shoes, but everything else about her is perfect!)
Picture Day Cleo (I wish the color of her shoes were a bit darker blue)
Sweet 1600 Draculaura (wish she had straight bangs instead of triangular)
Sig Nefera (don't like her headpiece)
BYBY Nefera (don't like her gold breastplate thingy)
Thankfully I can take those accessories off of Nefera so then she's perfect

EAH:
Sig Apple
Sig Ashlynn
Sig Maddie
Legacy Day Apple
Legacy Day Cerise
Thronecoming Cupid
The whole Hat Tastic line. They're all amazing!
Fairest on Ice Ashlynn
Fairest on Ice Duchess
Just Sweet Blondie (my favorite EAH doll!)
Dragon Games Darling
Dragon Games Raven (I originally didn't want her, but my sister bought her for me and I fell in love with her. This doll is seriously flawless, I love everything about her and I'm not even a huge Raven fan!)

ALMOST Flawless:
Sig Darling (would have liked her headpiece painted)
Thronecoming Blondie (would prefer her hair down instead of two buns. If I ever debox mine then she'll be getting a trip to the salon )
Through the Woods Ashlynn (wish her dress had a seam)
Birthday Ball Duchess and Blondie (painted accessories would have made them perfect!)

[nassib]

Since my collection is primarily Ghoulia, I would have to say the flawless beauties are SDCC Ghoulia - she is beyond gorgeous.

Totally agree with you.

[8BrickMario]

Unpopular opinion incoming...
Amanita Nightshade. I think she's just gorgeous. She pulls off a slightly eerie elegant look with her first doll, and her second doll is just as pretty, just a bit tidier. I think she's one of those characters that looks good no matter what.

Freak du Chic Twyla and Toralei also deserve mention.