Every missal and missalette publisher contributes their suggestions to the choice of readings for tomorrow’s American holiday. Some priests and liturgists vary from those offerings, and some readings pop up year after year. The Lectionary offers options for Masses of Thanksgiving, but I think the US observance has some unique qualities that should be included, mainly a sense of thanksgiving for our nation and culture.
My suggestion would be to rotate three sets of readings, cycling through along with the ABC structure of the liturgical year.
Deuteronomy 8:7-18 (It’s a good land, but don’t get too haughty and unmindful of God); Psalm 34 (Taste and see the goodness of the Lord); Romans 1:8-12; Matthew 11:25-27 (Jesus’ prayer of thanksgiving to the Father)
1 Kings 8:55-61 (King Solomon gives thanks); Psalm 145 (I will praise your name, my King and my God); Colossians 3:12-17; Luke 1:39-55 (Visitation & Magnificat, a substitute for Mark)
1 Chronicles 29:11-18 (David’s canticle of praise); Psalm 100 (We are God’s people, the flock he tends); 2 Timothy 1:3-10; Luke 17:11-19