That'd be nice. I think more characters in general would be good though, since it's been a while now. They add so much content to the game just by their inclusion and it can make things pretty fresh, but I understand not wanting to change the original layout of the town. I think a good balance of this might be adding a new side region much like the desert and having a couple of people live there that are marriageable. Possibly a wooded area since the new update hints already is going to include at least one new fruit tree.
I'd also be a huge fan of Sandy's story being expanded. And dating her. Mostly dating her.