Game Idea: Crafting

Crafting in modern games absolutely not realistic. I mean it looks more like trading where resources needed to build something is money and blueprint is trader. Also there is no fun of real crafting where you can do something in may ways or replace one components with the other and have logical structure of what you doing like actual design do. The only way to really craft something inside game - circuit simulation algorithm where you can build some scheme and test in on your pc or coding. But of course it is much more complicated to make and may not be popular because of complexity. Probably it can be replaces with some kind of LEGO or PlusPlus idea where crafting is simplified  a lot for people.