very interesting post. recently I had to migrate some tables from Vertica to Aurora Serverless because we were building an internal tool and we needed more separation between those tables and the rest of the DWH. Unfortunately, i did not have the time to the Data Migration Service from AWS and since the tables were quite small anyway we went for a naive manual process. I will definitely have a deeper read at your other posts!
But I must say that the setup and use of Aurora Serverless, especially via the serverless yml has been a breeze!