I really liked this concept! And linking things together and seeing an outcome and the progress of the city was cool.
Two problems:
The linker being a raycasted line and not just where I'm pointing is annoying, I kept grabbing things I didn't want. In fact, it may have been better to just not have moving around be a thing, just click on two objects on the screen.
The possibilities for combinations are limitless, and the combinations I would come up with in my head are not the same as yours. Sometimes combinations would make sense, fire and beef make a steak. But sword and bush make cactus? Abstract thinking there, and it lead me to things like, maybe fire and snowman would make water, or stone and guitar would make rock music. It was really hard to think of combinations to do.
Good concept, would love to see it in a more fleshed out game.