Adding to the previous answer, I feel that usage with the so-called Japanese pronouns is somewhat of a special case. For one, the plural cannot be implied without adding a suffix. 私, 彼, 彼女 and あなた alone never mean (approximately) we, they or the plural you. Secondly, I don't think adding ～達 or ～等 has the nuance of putting an emphasis on any one individual in the group, as they do when used with other nouns.
Also, one more pluralizing method, though one that is used very restrictively - both in regard to vocabulary and style, is reduplication. It's used mostly with natural landmarks (山々、木々) and (in child-language and as a dual) body parts (目々 etc.).