Anything from Leader Games and illustrated by Kyle Ferrin (Root, Oath, Fort…) feels like cheating but still, I absolutely adore their art style
Everdell, Photosynthesis, Parks, look nice as well
I also bought an updated edition of Costa Tuna just because of the illustrations: https://www.pamwishbow.com/client-work/project-four-yjynj-pafyx
When it comes to card art definitely Dixit. When I Dream also has really nice illustrations (and is pretty fun too).
Dixit sure had to be mentioned - when art is effectively your game mechanic it needs to be good. Though it depends on the card set, not a fan of the Dixit Odysey base set
dude, I LOVE When I Dream! Also the idea of putting the draw pile inside a bedframe and covering the unused top of the cards with a pillow is so genius and creative!
Ooh I had totally forgotten about the pillow thing. Yeah that bedframe is pretty cool
I also played Mysterium
which was made by the same people behind Dixit(I just checked and not at all, it’s just the same mechanics with beautiful illustrations open to interpretation, my bad), and the game is a lot more engaging to me, but Dixit is one of the classics for french players!