Rambles from a fully integrated plural system
The wonderful thing about plurality is that it's so subjective. Your experiences are entirely unique and you won't find something exactly the same as it, although there's probably lots of similar ones out there! The same goes for the language we use to talk about these experiences.
Archiving plural history is a hobby of mine. Seeing how common lingo has changed over time, grown and evolved inside of different plural groups, is really interesting to me.
To some people, they prefer the term "multiplicity" over plurality. We know that many multiples continued using the phrasing of multiple personalities past the diagnostic change from MPD to DID. Back in the 2000s, so many plural webpages favored the term "household" instead of system (which I think is adorable). I see lots of collectives go by, well, "collective" nowadays, too. There are probably hundreds of terms to describe parts, just in general and based on perceived roles, origins, and aspects: alters, headmates, parts, people, insiders, littles, bigs, protectors, persecutors, hosts, cores, walk-ins, soulbonds, willomates, tulpas, fictives, factives, introjects, and so on.
Of course, because plurality is so personal and subjective, we all have terms that we simply don't vibe with. It just doesn't fit. I used to loathe the term "plural" itself because I couldn't possibly see how it fit me. But as we grow and change, the way we perceive and talk about our experiences might as well. It certainly did for me! After our final fusion we came to love the term. Funny how that works?
Throughout my time in the plural community, and beyond that as I collect archives, I've seen many debates over certain terms. Lots of these personal identifiers have been deemed universally bad or wrong. People who identify with them are unfairly told to stop. I think because some folks find certain terms to be hurtful or uncomfortable, they come to the conclusion that it must be that way for everyone. But that's just not how it works!
Two terms that I love are "parts" and "people." We've always used both of these words for ourselves. I'm a part, a person, a part of a person, and a person composed of parts!
A lot of plurals see "parts" and "people" as polarizing opposites, though; mutually exclusive. I have met systems who were vehemently against using one or the other. Discourses on people versus parts language are often intermixed with other discourses on plurality, so that becomes a stereotype for people who use these terms.
One preconceived notion I see about describing your system's people as "parts" is that it's dehumanizing. I see similar debates in the queer community when it comes to using it/its pronouns. I find it really silly. Of course I'm not dehumanizing myself...but if I was, is that really so bad? I'm happy, so why does it matter?
I don't think considering yourself a part or a person is mutually exclusive. We're all a part of something, plural or not, and that doesn't erase our personhood. I am a part of a system in the same way I am part of a family and part of a community. To me, calling ourselves parts acknowledges that we are equally important in this shared mind.
Additionally, some of us in the system never felt like full people. If we called them people, it would just be flat out wrong and send them into a spiraling panic. Being a "part" meant that they were valued no differently from the rest of us, because we were all parts. They were complete as they were, regardless if they went on to become more developed members of the system or stayed the same. But if they had to only be "people" then they'd feel like they weren't complete at all and didn't belong. It would drive a wedge between them and all the rest of us. Respecting their desire to be called parts feels way more humanizing than forcing the wrong language onto them, doesn't it?
Calling us "people" at times is very important, too, because we are a system in the same way we are a person. The idea of being a person is an understandably complicated subject when it comes to plurality. To put my views very simply: discounting any one of us or treating someone as more real than the others would not be treating us as a full person. It would be a denial of the personhood that we share equal claim to. That includes discounting our individuality as members of a system.
Another preconceived notion I see about describing your parts as "people" is that it will only increase dissociation. I find this silly, too, because any word can theoretically trigger dissociation. What matters is if it's actually doing that or not. How is someone supposed to figure out for themselves what helps or harms them if they're told how someone else thinks it should work for them?
Do the words matter so much as the experiences that lay beneath?