It's going to vary based on personality, unfortunately.
Some individuals of some species will seem to get along better with others...
I've 4 parrots (see list above).
Scooter bonds with Rusty but will allopreen Rosie.
Rosie will fight Rusty whenever (s)he gets a chance. And Rusty loves to invade Rosie's territory.
Rusty and Scooter allopreen me.
Rosie is scared of human hands, but always hangs upside down or does somersaults to gain and maintain my attention. I know she has issues, but she's overcome a LOT of them and has bonded as much as her damaged psyche can allow her to do.
Tybbi is too new but he has shown territorial aggression against Rusty and Scooter, but Scooter too has shown aggression (probably territorial). I'm not trying with Rosie.
Maybe with time, I can get (most) of them to be out of their cages at the same time, but for now I "timeshare"...
My parents have cats. Once they brought in another as a rescue. The new one terrified the two existing ones, so the new one went back to the agency. Years later, one died so they adopted two kittens. The other old cat, who was a rescue from an abusive environment, is bothered by the newbies because they want to play and he doesn't (and one of the newbies wants to be dominant...) It's been 3 weeks and the old one has been slow to change, but some progress has been made. I'm keeping my fingers crossed for them...
Sadly, the only pet that gets along with everyone is a dust mite.
