NT Wright, who admits up front that we should exercise caution, suggests that the list of names in Romans 16:1-16 points to the social make-up and to the number of house groups in Rome. He sees five or six house groups: Phoebe, Prisca/Aquila, Aristobulus, Narcissus, Asyncritus… brothers with them, etc.
Wright suggests that each house group had between 6 and 20 — leading to between 30 and 120 in Rome.
If the Jewish names indicate Jewish-Christians, then we might have a “weak” and “strong” indicator.

There are “missionaries” among the Christians in Rome.
There are plenty of women mentioned, some clearly as leaders: Phoebe, Prisca, and Junias.
Denny Burk informs me that John Piper has a sermon about the greetings of Paul. Here’s Denny’s note to me:
What’s the point of a greeting? The greeting is just words. We know that is not the main thing being carried from Paul to these people. What is being carried is love. Four times he says it explicitly. Verse 5: “my beloved.” Verse 8: “my beloved.” Verse 9: “my beloved.” Verse 12: “the beloved.” Paul loves these people, and that is what this text expresses. The point of this text is: I love these people, and I want my love to be carried from my heart to their heart by you. So would you please take these words from me and make them the bottle from which you pour my love into their lives?
Whatever else we may learn or experience in reading these verses, let us not miss this most obvious and important experience: The preciousness of Christians in the hearts of Christians.
So let’s do three things with this truth that Christians are precious to Christians. First, let’s consider one expression of it in the holy kiss. Second, let’s remember the foundation of it in the death of Christ and our union with him. Third, let’s consider the intensification of it—the kind of things that more deeply endear one Christian to another.”