Does rare convey a negative meaning?
It could, but doesn't have to.
I presume you might be Spanish, because of Raro's negative sense.
Alle tradisjoner overalt virker rart for utenforstående :)
Does "unusual" not work as a translation for "rare"?
'unusual' = 'uvanlig'
I first translated "menneskene" as "peoples", which would make sense in English ("these peoples" = "these nations", or "these tribes"). Does this also work in Norwegian?