Real tree branches make great roosts. I have them all over the run kinda like a jungle gym. I've seen people hang swings too lol. Tires filled with dust or ash. Mine love to get on and poop all over the rod iron table when there free ranging.
They also like boulders to sit on, you can make them a dust pit in an old sandbox. Some of the parrot toys are good for chickens and made for much stronger beaks, so should last a long time. Even a brightly colored ball can be fun to push around.