Build a good foundation and the rest will be easier. For future systems text during h-scenes and multiple different stages for each scene would be great, they improve the experience significantly for me personally. A lot of stages can compensate for no dialogue though, Wild Life is a good example of that, though its probably quite intensive work wise because of all the animations for each scene.Hey, I am not familiar with these games, but my plan is to build a sandbox where some people can create and some people can consume.
I already made an in-game level editor that will work hand in hand with the ModKit (which will allow you to import stuff) the aim is to make it as easy as possible to add something new - and finally the Scripting which will allow to create any sort of gameplay you can imagine.
Random example: You download some houses as `.fbx` straight from internet into the game mods folder (ModKit does the heavy work). Using scripting and the in-game editor you could make a "Conquer Your Neighbourgood".
Once the game have all this functionality ready I will provide a couple minigames from time to time
You probably already have this planned/added but being able to import custom animations/h-scenes would be great.