I find turkey poults extremely easy to get started. They are the ones teaching the chicks where the feed and water is. Last year I couldn't get high protein starter easily, so I raise a bunch (30+) poults with the chicks on 20% starter. They did great and the ones I didn't sell are now running around the farm like they hold title to it.
They are the first ones over the top of the brooder, as you mentioned. I think they get bored and/or lonely for people and go exploring. I could always tell when one went over the wall because they would get really loud trying to get their mother or siblings to come rescue them (which I did, of course).
I usually house extra roos in my turkey pen. That only went sideways once, but works fine almost all the time.
I tell people that chickens are the "gateway poultry" to turkeys. Once you try turkeys, it is hard to go back to only chickens.