Is there any significance to the fact that Paul did not prioritize Rome as the capital of the empire in his travels?

The specific way in which Paul writes concerning his travel plans forces the Roman readers of his letter to become humble before the face of God. They must remain aware of the fact that Rome is but one city in the queue: This is the reason why I have so often been hindered from coming to you. But now, since I no longer have any room for work in these regions, and since I have longed for many years to come to you, I hope to see you in passing as I go to Spain, and to be helped on my journey there by you, once I have enjoyed your company for a while (Romans 15:22–24). The readers not only have to tolerate that Paul is not going to settle in Rome and plans only to visit them in passing, they must also have a positive attitude about it. The apostle expects them to help him on his journey to Spain. He counts on the Christians in Rome to be of service to him in the preaching of the good news out of Jerusalem (and not out of Rome) to all peoples.¹