There are obviously certain parts that are necessary to weave this story. I have listed some of them below, along with some random thoughts on the characters. All is open to discussion of course.

I am less sure of the personalities of the archaeologists we posit as having found evidence of our characters. But we can discuss that later as well.

Main characters:

Elimilech - Patriarch of the family. An old man, he has been weakened by the famine and is mortally ill.
Naomi - Matriarch, and true head of the family. She is quiet, strong, and capable.
Mahlon - Elder son, husband-to-be of Ruth, metalsmith
Chilion - Younger son, husband-to-be of Orpah, metalsmith
Ruth - Edomite living in Moab, priestess of Chemosh
Orpah - Edomite living in Moab, priestess of Chemosh
Boaz - Israelite farmer, cousin of Elimilech
Tamar - Boaz' wife
Tob - Israelite merchant, cousin of Elimilech

Possible characters:

Zebushar - King of Moab
Akton - Zebushar's son

Adversary of Mahlon, Chilion, Boaz... perhaps Hedak?
Lieutenants of same

Bethlehemite (Judea) population... shopkeepers, farmers, families, etc. possibly aligned either with Boaz or Tob

Heshbon (Moab) population... shopkeepers, farmers, customers, families, etc.