These are too good. I like how for all of these different styles so far, it's at least making an honest attempt to match them, and that painting you specifically highlighted is excellent (as much as I don't think they're quite playing poker as I know it). If you haven't hit your tolerance of poker-playing penguins, how about "penguins playing poker, in the style of Rene Magritte's 'The Son of Man'" (my friend's suggestion) and "penguins playing poker, in the style of The Simpsons"?
My original rationale with penguins as a subject is that they're black-and-white bipedal creatures, so hopefully not too hard to draw doing human-like things, that also aren't likely to have much existing artwork of them out there. The drawings I could find of penguins playing poker online were far worse IMO than any of these.
If I had to guess, it was that it was going for a painting before versus the broader style and the texturing got messed up. That probably implies that it's better to simply prompt with the style of painting you want instead of asking specifically for a painting, if you want coherent results.
I also think it's interesting to note that with the second prompt, DALLE struggles immensely to figure out what belongs on a table when playing poker than compared to the first, supporting your assertion that the more complicated scene causes some details to collapse.
If you're still taking suggestions for prompts, I think these turned out so well I'd be curious to explore more variations on the theme. Could you try "penguins playing poker, in the style of Salvador Dali's 'The Persistence of Memory'" and "penguins playing poker, in the style of Grant Wood's 'American Gothic'"? These should be styles it can handle well that purposely aren't suited to this subject matter.
Thanks to Benjamin Hilton on Twitter, I've been able to run some prompts despite not having access to DALLE 2 personally, and we noticed some interesting edge cases with DALLE's facial filter. Obviously in general DALLE is fine with animal faces and not fine with human faces, but there was one prompt I suggested, "a painting of a penguin jazz band, in the style of Edward Hopper's 'Nighthawks,'" that gave a bunch of penguins with eldritch abominations of faces. Another prompt, "a painting of a penguin in a suit, in ukiyo-e style," had no issues with generating proper human faces.
This makes me wonder if there are other ways of getting non-humans to be flagged as human, given that there's no particular reason stylistically why DALLE couldn't execute these generations with non-eldritch faces—or if it is actually the artistic style that caused the problem. Could you try "penguins playing poker" and "penguins playing poker, in the style of Edward Hopper's 'Nighthawks'" to see if the art style is at fault?
I've never seen that degree of screw-up in any DALLE generation before. Wonder what could have happened there.
So I think that's the extent of "penguins playing poker" as an artistic subject for now (although it was very nice seeing the contrasts in style, and if I ever get access to DALLE myself there are some other variations I might try), so I'm curious now to see what exactly the limits of penguin generation can be (and perhaps if anything trips the content filters). There's this lovely Claymation sketch on YouTube that remakes The Thing with Pingu, so I'd be curious to see if DALLE can handle "penguins in John Carpenter's 'The Thing'" or 'penguins in the chestburster scene from Alien". I suspect these might be too complex/specific for it to handle, but if either of them were to work... a third one that could be worth a try, too, is "penguins performing an exorcism".