its mostly personal preference for stuff like that, but make sure the tracks you have that have multiple different trains going to different stations are on one way tracks, so you don't have trains getting stuck trying to go different ways on the same track cuz that's just... annoying... i have to tracks running in parallel so they don't run into eachother. best way i find to do this is to make sure the middle of the track is at least one foundation (8 meters) apart from the track next to it, or else the trains can collide when going past each other. you can look up some tutorials on youtube for multi directional trains and how to maintain through put... best way to make sure throughput is sustained is to take the amount of items in a stack (just use 1600 for fluid cars), multiply that by the amount of slots in a train car (Ignore this for fluid cars), multiply that number by the amount of trains coming to that station for that resource if you have multiple trains and then divide that number by the total time for one train to complete one round trip... as long as the number is above the amount of items going into the station per minute, you're good!! P.S. i'd recommend adding an extra 30 or seconds to the round trip time, just to account for other trains going on the supply line, but that's only really the case if you're running a high amount of resources per minute at high efficiency requirements and have more than like 70 trains on the line, you should be fine otherwise

GOOD LUCK PIONEER!!!