The main thing I'm looking for is something super detailed, almost painting-like...so along the lines of The Pale Horse and Peak (IM Gang-hyeok). But... I know there might not be other works in that vein so I'm not expecting that much.

More typically manga-esque type art styles are good too... Like in Kisswood or A Fairytale for the Demon Lord... as long as there's consistency and detail.

Other pretty good examples:
Nineteen, Twenty-One & other works by KIM Hye-Jin
Pink Lady from what I remember
Diamond Dust (KANG Hyung-Gyu)

Thanks much in advance.

I enjoy the art of all the webtoons I read, but as far as picture-esque type I can really only think of Orange Marmalade. It's a romance but the scenery panels are really beautiful.

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WEBTOONS ヽ( ★ω★)ノ

Of the top of my head, I'd have to say Noblesse. Quite good artwork and awesome story line.

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No matter how messed up you are in your life, just remember that your story is still better than the Twilight series.

Seconding Noblesse (the art improves immensely as you read on).

Girls of the Wild's has some pretty art too.

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Is this me in a nutshell?
Pretty much.

This is... pretty subjective, so apologies if my suggestions don't fit your tastes.

Lessa
Song of the Cloud
Twelve Nights