Thank you very much for the reply. So far Pi, has gotten on very well the the Parrotlets. I think it works out fairly well because plumheads are so gregarious and not really territorial. The forage together and chat together. They also look out of the window together. The biggest problem I have is that the parrotlets wiggle dance for Pi and try to get sexy with him. Pi has no idea what all the fuss is about and is not interested. He just opens his beak at them and lowers his head, trying to point out he is not interested. Neptune tries to get help with pin feathers from Pi, which is another thing Pi would rather not be involved with. Pi can get frustrated with it, but his reaction is safe and he is a very peaceful temperament. So far the communication gap between the species has been peacefully resolved, but I am always supervising them.
Kakariki are very stunning. Bulling may cause the parrotlets to have some sort of parrot battle...hummm My lovely feisty boys.
For now I will keep watching kakariki beauty via lovely Riti. She is such a doll! I am sure once you make that breakthrough in hand trust it will really take off. Birds always seem to really excel once they have that 'Ah Ha!' moment and realise this human can be trusted.