Are those California cages? Just seeing if I'm as familiar with birds as I used to be

I share the same views with Popcornbird. There are certain emotional needs that a single human cannot possible provide. For example, 24/7 companionship. This is a true gem that a birdie friend can provide, but a human could not. Birds are gregarious flock animals and need the constant companionship, which is why you always hear of neurotic, abandoned Toos and such. My suggestion for you is to get two handfed Cockatiels and spend as much time as possible with the two. You must remember that birds are handfed in clutches, so they've been accustomed to relying on humans and viewing them as friends, but socializing with their birdie companions as well. I admit that I do have a single male Cockatiel, but his cage is next to my flock of budgies, so, in a sense, he does have that constant avian companionship.

Any of those cages are fine. I was never told that dome-shaped tops were hazardous for tiels. I was only told to stay away from round and cylandrical cages because they do not provide an opportunity for the tiel to hide. I don't see how dome-tops can do this, but I've been proven wrong more than once

Edit: Now that I think about it more and more, I believe it was recommended to avoid cages with playpens on top since that can contribute to cage aggression...I'm trying to recollect a vague memory, so I may be wrong. But if I am correct, I'd try to see if there was a cage like #2 without the playpen on top.