anyway ive been thinking and, putting all my cards on the table, generally i tend to view plurality and polyamory both as occupying this kind of space of being less "thing that is essentially true about you" and more "alternative frameworks for understanding the world that rely less on normative assumptions".
polyamory being less about "being someone who experiences multiple romantic attractions simultaneously" and more about rejecting the core assumptions of monogamy as bolstered by the societal regime of heterosexuality. similarly i tend to think plurality is less about "experiencing multiple selves" and more about rejecting the core assumptions of singularity as bolstered by the societal regime of saneism.
i think how you organize your experiences of attraction and relationships can conform to the monogamous model quite easily, and forcing it to do so is generally socially beneficial to you, thus if your experiences lean closer it's easy to let them just stall and not do further introspection. but introspection and self-critique is always useful, so i recommend more elaborate analyses at every opportunity. thus, i think the "no assumptions, figure it out yourself" model of polyamory that prioritizes granting tools over making assumptions tends to be more useful. of course, if your relationships can conform to monogamy, you receive increased legitimacy, legal benefits, heightened trust from monogamous ppl, and less weird questions, among other things. so like, i think i can really only make claims and arguments about tools of self analysis.
similarly, i think how you organize your experiences of identity and selfhood can conform to the singular model quite easily, and forcing it to do so is generally socially beneficial. i think generally 'plurality' is first understood as only describing those who are totally unable to conform to this model, but i think as with all deviation from the norm, more questions than "are you totally incapable of conformity" should be asked. in all of my experiences, i have seen time and time again that some level of apparent plurality seems to be a normal expected part of the human experience. worksonas, code switching, drunk identity, hell even some subspaces all seem to exist on the same spectrum as plurality. but, over and over i see these different states of self be basically insulated from introspection or individual analysis by a rejection of plurality/assumption of singularity. when performing analysis of the self, i think one must not ask "is this correct", but rather "is this useful".
both of these are rather controversial claims, as a basic form of assimilationism is the claim that your status as "different" was always obvious and incontrovertibly true, ie the rejection of social reproduction. also, i'm a queer not-quite-person with so many things wrong with me so i do have a biased perspective. i cannot and should not claim that my experiences can be generalized. unlike me, most of you are probably capable of believing that you are, and convincingly passing as, sane. further, like, truly, maybe i'm wrong and there are essential differences. in the past this spectrum argument has been tried and failed disastrously for some groups while it's succeeded wonderfully for others, but i think it should always be considered.