Some other Scriptures to consider Pastor, I am appreciative of your stated desire to honor God and be faithful to the Scriptures. All of us who believe share the common challenge of interpreting the Scriptures accurately. In simple terms, the ultimate test for the Bible student is to discern what portions of Scripture are prescriptive (declaring what must be done), and what portions of Scripture are descriptive (describing what was done).
I believe that your message came from a good heart. But I am perplexed at how you could draw your conclusions considering the full witness of the Bible. "Hymn" or "hymns" occurs more times in the New Testament than "psalm" or "psalms" (seven vs. six). Immediately after instituting the Lord's Supper, Jesus and the disciples sang a hymn (not a psalm). Paul's and Silas' jailhouse worship included singing hymns -- and there was some rocking and rolling going on as a result (I couldn't resist).
The result of Christ's becoming servant to the Jews was to confirm the promises made to the patriarchs, and open the way for you and me (among the Gentiles mentioned) in order that we may "glorify God for his mercy, as it is written:
“Therefore I will praise you among the Gentiles;
I will sing hymns to your name.” (Rom. 15:9)
Note the word "hymns," not psalms.