Do not recommend main bus design to new players! The most fun I've in Factorio had was getting to a rocket blind and dealing with my spaghetti factory. Even mentioning any kind of pattern to new players should be avoided.
I avoided a main bus after noticing nearly all the copper went to producing circuits and low density structure, and similarly most iron for steel and green circuits - so just site those close together linked via short buses [1]. Then ship the remaining copper, iron and steel to the Science factory using single wagon trains. (That’s just for a simple one rocket per hour factory)
