You’re right in that knowing pronouns is sufficient to determine grammatical gender of words to be used with relation to a character in Russian. Combining a particular gender of pronoun with an unmatching form of verbs/nouns/etc is definitely not a part of the language, even outside some formal norms.
One possibly unobvious thing is, though - there are only three grammatical genders in Russian, so all words which do have gendered forms can have at max 3 of them (male/female/neuter). This means that if you do allow more than 3 kinds of pronouns, you’ll probably have to define the pronouns->grammatical gender mapping somehow. Well, I guess plural variant also counts, so maybe 4.
One possibly unobvious thing is, though - there are only three grammatical genders in Russian, so all words which do have gendered forms can have at max 3 of them (male/female/neuter). This means that if you do allow more than 3 kinds of pronouns, you’ll probably have to define the pronouns->grammatical gender mapping somehow. Well, I guess plural variant also counts, so maybe 4.