If gender, ethnicity, age and inhibitions don't matter, then let's say accents don't matter either. I'd play Alma.
I don't think she's as boring as some might think. She's loving and patient, and willing to endure much (much more than I am) - but she also tells Ennis she'd love to have more of his babies if he could support them, she yells at him that supper's on the stove, she's the one who finally gets out of that unhappy marriage (even though with Monroe as backup) and she finally, finally confronts him on Thanksgiving.