I think Fiona is the spunkiest character by far, but I have to say Ben and Asher are the winners for the best characters. They are such a beautiful couple and the picture of them that Rano did is wonderful. Really brings them to life! But you've made Bernie and Martha likeable too, and they surely have a story of their own as well.
Yes, you could do a lot to bring Tommy into the story. He is an interesting character with an interesting past, so that could be added in too and capitalized on. Also there's some reason for him being single at this point. How old is he anyway? Definitely lots of questions about him. Then he disappears to visit his friend. Who is this friend? Do we know whether it is male or female even?
There's also all the other youngsters in the village that haven't yet been properly introduced and exploited. So plenty of development that can still be explored.