I'm currently involved in an amateur project to make a game in the tradition of Stardew Valley and the Harvest Moon/Rune Factory series. We've also looked at sandbox MMOs like A Tale in the Desert and Wurm Online for ideas, as well as games focused on animal breeding and fishing.
So I've worked through most of my own ideas and asked my teammates for theirs, now you all can have a chance to have your opinions taken into consideration. Please don't describe any ideas you want to retain intellectual property rights to, we're not paying you. But other than that, if there's anything you've particularly liked in a previous game that would fit into this kind of farming-rpg-dating sim thing, any character archetype you'd particularly like to see in the game, etc, tell me about it.
For clarification, the kind of game we are making is specifically a single-player 2D sandpark game. The world is specifically a fantasy world, and the player can learn combat magic along with physical combat, animal breeding, farming, fishing, cooking, mining, crafting buildings and appliances, and there's some romance and politics in there too.
If anyone is so taken with this game idea that you want to participate or support it somehow, send me a PM.
I want to help design and develop a PvE-focused, solo-friendly, sandpark MMO which combines crafting, monster hunting, and story. So PM me if you are starting one.