whatsarobot there are a bunch of roblox games similar to what you describe that take place in various playgroundy environments, e.g. ball pits and mcdonalds play place tube mazes. of course, only the most iconoclastic of insert credit forum posters would ever argue these are “beautiful.”
my half baked idea is a two player dating sim where each person designs/trains love interests for the other person to pursue. i suppose the target audience would be couples, especially those in long distance relationships who can’t actually be together physically. i’m imagining something asynchronous, since that works better if the players are in different timezones. half of the game would be a single player experience where you “train” your character, maybe answer a bunch of personality quiz questions, engage in certain challenges, decide stats to boost, and write free form text responses to certain prompts. the other half would be guiding your character through dates with the other person’s character. maybe you get asked a question and if you pick an answer your partner marked as bad their character starts to hate your character a little bit. maybe your character says weird stuff out of context based on a prompt you answered 6 months ago and forgot about. that sort of thing.
…actually this sounds a lot like tomodachi life, but as a dating sim. the idea is that your characters aren’t necessarily you. they have a life of their own, but that life feels in some way derived from your personality, so when you and your partner’s character go on dates together, you feel like you are exploring some corner of their mental world that you wouldn’t get access to otherwise. and perhaps more importantly, it would give you both another thing to talk about. the areas could all be various degrees of quirky with interesting npcs that your two characters interact with. it might be fun to talk about how, say, your partner’s character got in a fight with the hairdresser, who in response stabbed them in the eye with a pair of scissors, and now their character has to wear an eyepatch. stuff like that.