I think it would also be hard to sustain a storyline with him. I mean, you can do something with him meeting the family and the parents having their attitudes changed. (Wasn't there a famous movie in the 60's about this?) What about society, though? Even Northerners could be very racist, as we saw. So any relationship between Laura and Joe would be one long struggle against prejuidice. How long could you hold viewers' interest with that?