You state that él is a 'subject personal pronoun', but it seems worth mentioning that él is not always the subject, it can be an object or another role. I'm not sure what term is best to describe that... Wiktionary says it's a "subject and disjunctive pronoun (used as a subject and after prepositions)"
Examples where it is not the subject of the sentence:
'Voy a hablar con él.'
'A él le gustan los perros.'
