I plan to add some indoor aviaries side to side for Jaid and my conure in my own place when I move out and settle. That's going to be a looooong time from now, but it never hurts to dream.
I would add a few hanging things from the ceiling if you can. Like boings or swings. Also, if you're allowed, wall perches? They really can fill up a room without having the floor and walking space cluttered. And I would definitely go with like a natural wood playstand. I have a horrible one I made years ago, but I would like a bigger one for my flock now since I have bigger birds. Also, bird safe plants provide a nice aesthetic