It's all fine, actually. Different family groups will stick together, sometimes for a long time. And I think your roosts are fine too. If you had huge Jersey Giants or Brahmas, some lower roosts would be good, but you do have lower roosts anyway.
It's about status, family groups, and the time it takes your younger birds to fit in better.
The only thing that might help a bit is to block access to the nest boxes, and then only if you get out there early every morning to open them up first thing.
Otherwise, see how they do in another month or three.
My youngsters are doing many of the same things right now, and over time, they will do better.
You can try to place the roosting birds in more appropriate locations at night for a few days, and see it that helps.
Mary
It's about status, family groups, and the time it takes your younger birds to fit in better.
The only thing that might help a bit is to block access to the nest boxes, and then only if you get out there early every morning to open them up first thing.
Otherwise, see how they do in another month or three.
My youngsters are doing many of the same things right now, and over time, they will do better.
You can try to place the roosting birds in more appropriate locations at night for a few days, and see it that helps.
Mary