If I remember well, ''oni'' is the masculin ''they'' and one is the feminine?
I understand them like the French ''ils'' and ''elles''. You use ''ils (oni)'' for a group of men and ''elles (one)'' for a group of women. But if there's one man in a group of women, then you would use ''ils (oni)''
For people- yes
For nouns in general-
oni is for masculine personal nouns ( people, the rules like you said)
one: - masculine not personal nouns (ex dogs=psy, tables=stoły) - all feminine nouns (personal or not) - all neuter nouns (personal or not)
sometimes the way you refer to people and animals depends on the words you use:
dzieci - one (neuter noun), Kasia and Maciek- Oni;
psy - one (masculine not personal noun) , Fafik and Reksio- oni (male dog names)
Dwie osoby- one= dwoje ludzi - oni (osoba = feminine noun; ludzie- masculine personal noun)
Ok. In Serbian, you could say the same "Muškarci moji, žene tvoje!", but you could also say"Muškarci meni, žene tebi!". That's because we have short and emphasized forms of "to me" and "to you" - "meni - mi", "tebi - ti". I guess it wouldn't make much sense to say "Mężczyźni mnie, kobiety ty!" :D