I am open to suggestions. But this is for when I get my own house much later on. I plan to "improve" my house with little handyman projects, since I am good with woodworking. I plan to do a few things since I will always see myself having one or all of the birds listed: cockatiel, budgie, lovebird or pionus... most likely for sure a tiel and a pionus. Now, I am not saying I will have a plethora of cash to spend on material, but rather find most of the material and do the labor myself. Here is one idea of mine:
Find old, safe wardrobe or cabinet and revamp it into a cage like so:

Does anyone have anything else that may be cool and functional? Although I do have a feeling the wardrobe cage may not last too long with naughty birds...