Integrate your modding community. Alot of companies try not to put there players home made mods in because they don't know about all the legal stuff. But if someone made a mod like The Wood mod, which adds trees, wood, and wooden furniture... and people seem to enjoy using it, then what better way to say thank you so much, then adding that exact feature into the game. You wouldn't have to steal there code specifically or you could simply ask the mod developer if you could use his code the developer to officially add there brilliant idea and hard work into a game they thoroughly enjoy playing.. i think if you start there you will see what people want.