I think that the personal references at the ends of the letters were additions to the original material in the second century. I think Paul's original messianic (for lack of a better terminology) outbursts were softened by these random allusions to fellow-workers and the reassuring reference to him "having friends and acquaintances." The original gnostic figure of "the apostle" was elusive and larger than life. He had no equal among those born of women. The new additions fall into a pattern of bringing this secret apostle down to earth. He was no longer remembered as sitting at the hand of God, a doppleganger for Christ. Now in the hands of the orthodox editors he was boring and ultimately bourgeois. He had a job and family. His madness was relegated to periodic "outbursts" - still strangely "captured" and preserved in the MSS and for which he infrequently apologized to his readership.Aquila and Priscilla are mentioned in Paul's letters they are not an invention by the author of Acts.
But if the real apostle was really ashamed of his ravings - why didn't he just edit out his boasts and shouts in his final draft? The MSS of the early Church were all like Adv Marc with the "multiple drafts/multiple editors" of its introduction. The question by the end of the second century was who (which tradition) had the best MSS? No one questioned the wide variation that existed between MSS and communities.
Acts fit the Pauline letters with the intention of making the apostle a caricature of his former self. He was now "a boasting windbag" with friends - a sociable mental case rather than a mere run of the mill mad messiah. The portrait in Acts was preferable to the historical lunatic megalomaniac who actually founded the Christian Church.