While Restaurant To Another World has a nice atmosphere and does well to protray a comfy setting, it's only purpose are the two things I mentioned: short meaningless vignettes that can sometimes be heartwarming, and watching people gush over the food that they love eating so much. While it does those two acceptably, there really isn't much else to this story. None of the main characters are developed. They have an episode half or two that gives them a little bit of character but for the most part they are ultimately unimportant. Just people that you get to know as you get to see the various walks of life that frequent the restaurant.
The various walks of life aren't very fleshed out either. While we are introduced to important bits of their character for that segment, this does very little but give a general sense of who this character is. In many cases, this character could be one of many others that would be able to fit into the role. Ultimately their personality doesn't matter and isn't explored. They are rather a tool to dig into what one type of typical fantasy character might enjoy at this restaurant. And due to a decent amount of the episode being decidated to their love and eating of the food in question, this limits even more the characterization that the characters get. While there are a couple who get developed to an amount that at least makes them a character, most of them are not.
The stories usually aren't that much to write home about either. Most of them follow the same ordering. First a problem or a character point or some sort of starting idea will be introduced. Then that character will find the door or will think about when they found the door. Then they'll visit the restaurant and proceed to gush over the food that they chose to order. If it's their first time they'll express disbelief about how for some reason this restaurant shouldn't be able to do the meal they want well before turning into putty when they experience the true power of the food that they soon devour down. And then they order seconds, thirds, and as many helpings as they possibly can. While this can get very boring and predictable, I will note that there are times where the show is able to use its formula well and tell an interesting or heartwarming tale. Although some of its better tales are when it ditches the formula and decides to go more freeform, espeically when it involves the main cast. The episodes surrounding the demon girl in particular were able to carve a nice simple heartwarming story. The type of story I had hoped and expected to see more of from the show.
Restaurant To Another World also can have the bad habit of trying to gimmick up some of its shorts in order to cover up it's formula some. However this only makes it worse as the while the formula isn't too annoying the gimmicks almost always are. There is one part in which it tries to present itself like a documentry. While it's a novel idea it ultimately fails to bring enjoyment because documentaries are best for when someone craves knowledge in a subject matter. It's hard to crave knowledge into a fictional subject matter that as a viewer I didn't even know about until that episode started. With no curiousity being built, there isn't any pay off.
The art and sound are both fine. They're both good for the atmosphere that the show is trying to envoke and thusly I think that ultimately they work. Although the OP is very out of place. Personally I'm actually quite fond of the sound cue that they use each time someone comes across the door. It's unique and it makes a sort of recurring sound that adds to the comfiness of the work. I tend to like traits that are allowed to be reused and be familiarized to the audience. It's like a little special trait to itself, and that's pretty cool!
Overall I feel one's enjoyment of this show is really going to depend on the answer to those first two questions. If you want to watch people love and nom on food, or if you like short comfy but meaningless stories you'll probably enjoy this despite it not having the best characters or story. But if you don't like that or don't really care for it, it'll seem tedious and repeative, as that's really the meat of what it has to offer. Personally I'm not the biggest fan of either. While I can enjoy meaningless short stories if they resonate, they rarely did for me. While I certainly understand there is an audience for this I am firmly not that audience as the flaws outweighted the strengths of the show for me. As a potential viewer you'll have to make the decision yourself. Do you think short comfy vignettes and food love can outweight it's lack of character or story depth? If so give a try. If not you're probably better off looking for another show.