Just to be clear: I'm not saying its necessarily a bad game, particularly in any objective sense. I'm saying that I really dislike it. I know people will watch tearjerkers and listen to sad music and a lot of other stuff so I get that there is room for this kind of thing.
I made a video and when the walrus tricked me (trick is a strong word, I sort of could tell that I wasn't supposed to take any deals but I wanted to see what would happen.) and the rope he set up just trapped me it was just too "in your face." I mean you could have made it so that he just didn't set up the rope, or that the rope doesn't work or something but he took the payment and used it to set up a game ending trap?
I'm a big fan of humor, and I know everyone differs on that front too, but I don't get the joke here. The characters are just being flatly mean to the player, and not even in a playful or fun way, just a psychopathic and sadistic "oh I took your stuff, that's life" which isn't something I find too amusing or humorous or even particularly realistic. You are in the Forrest of Pain and Misery where nothing goes right and you cannot win, a very real take on the world? I mean, when someone trips and falls on the street, which is part of life, I don't laugh. Its just an ugly part of reality.
But ask yourself this: once a player knows the trick, would they do the game over again? As in, all the characters are out to get the player, there is no way to have a happy ending, and the walking bits are long and tedious, but "thank you sir may I have another?"
So on your art style question: perhaps you should make the visuals black and white and get some sad violin music playing in the bg?
And the music I chose almost is humorous to me in how hammy it is in its sadness. The character who gets this song when he's bummed out is a damn superhero who can literally walk on water and no one likes him. Its total cheese. That's the kind of stuff that actually has an irony to it.
In Shakespeare, when Nick Bottom dies in the play within a play in Midsummer Night's Dream there actually is a joke to it: his death is a play on how absurd tearjerker dramatic moments are. He goes on and on about how he is going to die and what a horrible thing that is, and he almost dies and comes back to life and then dies again and so on. That's a joke.
Here we have a game that is tedious to play, somewhat monochrome and repetitive. The walking isn't fun or interesting. If I made a video of the game I would have to cut those parts out. Then we have these little interactions that are just "unpleasant" to phrase it as politely as I can. If you told me the game part was really entertaining then maybe you could layer on an ironically sad narrative as a joke but in its current state the game is just a major bummer.
I understand, we all have our life's problems and sometimes in harder times, we just want to escape that reality with a certain type of games, books, series, whatever we personally like. It happens to me too, I wouldn't watch a Lars Von Trier movie every day. But sometimes, when not going through too harsh times, I think it's good to also see entertainments that try to see reality as it is. At the opposite, I get annoyed when games or movies try to be too optimistic or generic, I feel they are empty and fake. I prefer arts that face reality and try to give a sense to it. I find this kind of art to be more meaningful and honest.
This is not reality, it is a very particular view that you happen to have. Its easy to say anything happy is escapism, and that its more real to focus on the sad bits because that's just the way it really is. And I feel bad that to you that is what reality is. But just to use the oldest adage in the world, some people see the glass as half empty and some see the glass as half full. You cannot claim that "the reality is that the glass is half empty and to view the glass optimistically is just a fantasy" when in essence your art is trying to convince people that pessimism is the correct and real point of view.
You are going to tell me that in Melancholia, where a literal planet of sadness comes in and eclipses the sun, and then crashes into earth killing everyone, that is realistic? "It happens man, happened 3 times last week."
You may not realize it, and a lot of artists have pushed for the idea that sad stuff is reality and meaningful and important and award worthy and so on, but the art we consume affects the flavor of the reality we experience. You could go through life saying that you aren't going to add any sauce to the food you consume b/c it is a fantastical lie we are just telling ourselves that the food tastes better. But the food does literally taste better with the proper seasoning. And when you pour a heap of sadness on food and season it wrong it tastes bad. That's life: you can push it in the direction you want.