1 is an open question, but it's an easier question than the ones related to emergence, since it reduces from "how do we detect emergence of consciousness" (to which people have settled for behavioral tests, hence the whole AI consciousness kerfuffle) to "how do we correlate physical coupling with assumed (human) consciousness." This framing admits study via sleep/brainwave/dreaming/sedation experiments, though there are still things like large scale quantum coupling we can't easily measure.
2 is a problem for any theory of consciousness.
Regarding 3, I'm not certain "complex things have complex consciousness" is assumed, at least not for all definitions of complex. A crystal might be very complex from a structural standpoint but simple from a temporal evolution standpoint. I don't think there's a unified panpsychist perspective there. From my perspective, it's more a parsimonious rejection of materialist emergence hypotheses than a definitive statement of knowledge.
2 is a problem for any theory of consciousness.
Regarding 3, I'm not certain "complex things have complex consciousness" is assumed, at least not for all definitions of complex. A crystal might be very complex from a structural standpoint but simple from a temporal evolution standpoint. I don't think there's a unified panpsychist perspective there. From my perspective, it's more a parsimonious rejection of materialist emergence hypotheses than a definitive statement of knowledge.