I really think that the problems that people so often speak of with caiques have more to do with the people then the caiques. I know it is not intentional and I do believe the stories they tell are true. However, there are just as many people who tell stories of caiques that are fantastic pets and who are no more difficult than living with any other parrot, these are people who have had their birds for 8, 12, 16 or more years. You can put me in the later category (just with fewer years). I have six. They are all between 4 and 4 and a half years old.
They do try to bite on occasion, but I rarely get bitten. I try to avoid anything that would trigger biting as it is not any fun for either of us.
They are not aggressive. They may defend their territory but it is part of their nature and it is their right, it makes them feel secure. I try not to invade their territory. This behavior is natural and part of what makes them who they are. In fact, since my birds are in pairs and raise babies from time to time this particular behavior is intensified during parts of the year. Still, I rarely get bitten.
They are not moody. They do have moods but I really can only guess what they are so I try not to put a label on it. I try and read their behavior to know how best to interact or not interact with them at a particular time.
I guess my advice is more about changing the mindset. I am not singling you out, I am sure in your research you have been taught to expect an evil, devil caique at some point. But there is a better way. Honestly, I have had many different types of parrots and caiques are not any more or less evil than the others
So hear is my long winded advice, since you asked. It's all about dealing with things before any problems develop.
I choose to expect a wild animal to be living in my house, I choose to create an environment where the said wild animals and I can coexist happily.
Some of the fundamental things I do are as follows. Even if you can't do them all, the ones you can do will go a long way.
Keep birds in pairs.
Use cages with dividers so that you (or your pet sitter) can service cages and dishes without having be in contact with the birds. This is not always necessary but it allows anyone to take care of the feeding and cleaning and prevents eager birds from getting out when I don't want them too. The advantage over external feeders is that you can service the entire cage as needed without letting birds out.
Train your parrot to go back to the cage for treats.
Train your bird to move to a different part of the cage for a treat.
Keep them flighted. Allow them to exercise.
Provide lots of toys and foraging opportunities.
Maintain a routine for feeding and sleeping.
Allow them a consistent 10 - 12 hours of sleep.
Do not make them step up if they do not want to, bribe them. Do not force them to go back to their cage, bribe them. Do not stimulate hormonal behavior by improper petting.
Deal with any undesirable behavior before it becomes a habit. The first step is to determine if it is a normal behavior that is to be expected (and accepted) or one that can be modified. Then figure out how you can modify the environment or change your behavior so as not to trigger the bird to do the thing you don't like
Are you getting the idea? You can't really change the bird but by changing the environment, including your own actions and those of others in the house, you can influence the behavior of the bird. Often in profound ways.
Don't let anyone handle your bird that does not know how to treat them. Do not let anyone yell at or tease your caique. Most people are happy to offer treats to birds who are in their cages. This also lets the bird warm up to them and you can decide if you want to let them be out and interact more closely.
Things that I love to do with my birds. Watch them play with toys, let them out to fly and play independently or with their buddies, give them spray baths or a wet wash cloth, provide foraging toys. They also love to be a part of cleaning, washing dishes or bird toy making. They love music or kids videos. My favorite thing to do is train them to do a trick or something useful like going in and out of a carrier or to their cage. Practicing recall training. Other tricks I've worked on are waving, turning around, hopping, hanging upside down, high five and playing in a towel.
I fully believe that birds, especially babies need to learn to spend time independent of people. This is especially true if they are lone birds but much easier to do if they have a buddy. They need a routine, eating, napping, playing and so on.
Try interacting from another room as well. Talk with them and call to them. Let them know you are still around. Teach them to be independent even if they are loose in the same room with you. When I am in the room with my birds they come and sit with me or they go off and play. I love both. I don't feel like they need me. If you need to feel needed, a dog makes a great pet, truly.
So now that I have my "well behaved" wild birds...They are noisy 2-3 times a day for a period of time. If I hear constant screaming there is most likely something wrong. Usually, a bird has gotten loose and it is upsetting the others. I always go check. If there is nothing wrong then I give them some foraging toys, new foot toys, a paper towel, fresh veggies or a spray bath. The idea is to give them something that takes awhile to do so they can forget about screaming. You need to have these activities established as part of the routine in order for this to work. Bathing is great because it leads to a lot of quiet preening afterwards.
Biting. Avoid it at all costs. Learn how to not trigger biting before it becomes a habit. Example: Never force your bird to step up. Imagine:
Me: "Here bird step up" (presenting my finger).
Bird: Stands and stares, makes no move towards me.
Me: I press my finger on his belly.
Bird: Tightens his grip on perch.
Me: Continues to press on belly lifting the bird up some while saying "step up, step up".
Bird: Grips perch tightly and tries to push my hand away with his beak.
Me: Reaches around to grab bird or continues to press belly...either way you know what comes next...
Bird: Chomp!!!!!
Me: What a stupid bird, no wonder why they call him Satan! Runs away bleeding.
Now whose fault was that. It was totally mine. And worst of all I just taught my bird in one very memorable lesson to bite me if he doesn't want to step up.
One or two more lessons and he will become exactly the bird I feared he would turn into. And the saddest part is that I won't even know why and I'll go about spreading the rumor that caiques are evil.
Again, there is hope. Baby caiques and even adults can learn to get along with us but it is us who has to take responsibility for making it work.
I am not sure if this is what you had in minds when you asked for advice.
Sorry for the earful it was meant to be helpful but before we can really work with a bird we need to accept that they are the sum of their experiences so we have to provide the environment and experience that will make them a joy to live with
Every day won't be perfect but then again what do ever is?