Besides lots of nudity, the unfinished and currently offline CG webcomic Dreamwalk Journal (and its ongoing and very much online Spin-OffNightshade the Merry Widow) depicts vast exterior and interior vistas on the insect-dominated world of Cyeatea. You don't suppose James Cameron was a fan, do you?
Dresden Codak, one of the few webcomics you'd actually want to hang on a wall. Artist Aaron Diaz actually draws the comics on the computer. When sold as prints, they are between four and six feet tall, sometimes bigger. They look amazing hung on a wall.
Question Duck has many gorgeous backdrop. Which have, of course, nothing to do with the question the duck asks.
Rice Boy and Order of Tales actively revel in this, having entire pages that are beautiful sweeping landscape drawings or are lots of little no-dialogue panels just showing the characters moving through the environment. This is much less of a problem than you'd think, since the comic generally updates with multiple pages at a time.
Although some of it isn't in the webcomic, Ava's Demon is definitely capable of this, such as here and here.
Stand Still, Stay Silent has gorgeousness all through it, in whatever backdrop the characters happen to find themselves in. From stunning natural landscapes and crumbling, Romantic-ethos ruins... to drool-worthy, working, Schizo Tech environments with complex floor-plans: it's all good.
A Redtails Dream is by the same author-artist as Stand Still, Stay Silent and offers stunning walks through highly varied dreamscapes. Even the downright scary ones happen to be very pretty. In their own way.
Minor example but every Amical's manor background in morphE contains at least one Amical painting (including some which only show up in C Gs). The reason for the trope is that every painting is a full sized image which is resized and skewed to be mostly impossible to see in the comic proper. The background artist drew them in livestream for the amusement of herself and the audience present. Examples to date include: Amical streaking through a field, Amical skiing past the Ski Free Yeti and Amical as a mermaid. Good luck spotting those details in the comic proper and to date no version has been shared outside of the live event.
Lackadaisy has some really beautiful sepia tone backgrounds. In general, Lackadaisy has really careful and detailed art, and the shading on the backgrounds is especially good.