Based upon the above context, the word paragon best means

Freeholders are settlers who own their land, and work that land. That is to say, instead of owning the land to rent or lease it, they actually live in the land, and make a living from the economic benefits that they can reap from the land.

This type of settler was very common in the United States, especially in regions like the Midwest and Appalachia, were homesteading and other government policies promoted the settling of families who were to own the lands to be settled.

According to Crevecoeur, these type of settler is virtuous because he or she develops a sense of belonging to the land, and a sense of responsibility as well.