Do you have any advice for 2-way trains+stations on one-way track?

Hi Fellow engineers

Long time player but first time doing space age, first run, currently at bots/yellow/purple and a quick redesign of nauvis.

Somewhere along the way I decided that since my old rail blueprint's were scrap, I would make new ones with double headed trains, 2 way stations, but stick to one way tracks (2 lane instead of 1 lane) for getting everywhere.

I have successfully worked out interrupts + wildcard trains + depos in semi-LTN style.

Signalling is not something I need help with (unless you know something re below)

However this is entirely new to me (avoided 2 headed trains in vanilla) so my question is: what advice / top tips / things to avoid do you have for me regarding this method of train-ing?

Also haven't decided yet on squares + roundabouts, rectangles + no-right-turns (that was my blueprint so preferably not this), hexagons + 3 way junctions, etc for layout, so any advice there too is helpful.