Great news on the adoption rather than purchase!!! Kudos to you for that!
Now, in my personal experience and for what I have read about the other species, all pyrrhuras are pretty similar when it comes to their personalities and they do tend to be super sweet IF taken good care of (and the IF is a real big one). They are Velcro birds in the sense that they want nothing more in life than to be with you so, in that sense, I guess you could call them demanding but they are not a pain in the neck about it because, as far as they are concerned, if they are riding your shoulder, cuddling against your neck, hiding under your hair on your nape or burrowed inside your shirt, they are in heaven. Now, cockatoos are also Velcro birds but they are a pain in the neck not allowing you to do much but to be with them. So, Velcro is not necessarily good or bad, it depends on the species. The 'IF' of the care is, actually, nothing more than the amount of out-of-cage time and how long they are on you. There are other factors like hormones but you already took care of everything else with your good plans for bird husbandry.
Go to a rescue and look for a sweet female GCC (they are always sweeter than the males but this is actually true of any species of parrot), and see if she is willing to come to you without hesitation and does not even beak the finger when you put it out to her and you will have found the perfect match IF what you want is a super cuddly bird and not an independent one.