Pellets just don't fit into the picture, according to that equation. Neither does any seed coated with FDA approved food coloring and preservatives. Think greens and berries. We obviously can't provide the exact source, but the best thing would be to opt for a very wide variety of fruits and vegetables, as well as a good seed mixture with dried fruits, vegetables, and even health enhancing herbs, rather than artificial vitamins. We can't exactly be expected to provide any of the other bugs or critters they may choose to eat in the wild.
Variety is also important, as they surely have that in nature, as well.
It would probably be worth the effort to go to your neighborhood library and read up on the vegetation of their native environments. Last but not least, yes, as much as you may try to discipline your bird, it may still bite you. It is a wild animal. No matter how we have domesticated it, it is still wild. Dogs and cats have been domesticated for thousands of years and they still can give you a nice nip or two.