Having all the roosts at the same height works the best.
As well as having enough roost space for everyone on a single bar.
1ft+ for each bird.
My coop was made with pallets and the roost bar isn’t even ever used.
The majority roost on the highest plank that attaches to the ceiling arches.
The rest sleep on varying levels of the pallets. The lead cockerel sleeps on the highest pallet on the far side so he can see everyone. The chicks roost on the highest pallet and some roost on the ceiling plank.
The whole interior of my coop is roosting spots so I’m ultimately going to remove the actual roost bar I put in but I’ll wait maybe in winter they will use it to huddle together